Visible light communication of an access credential in an access control system

ABSTRACT

Techniques are disclosed relating to communication of authentication information in an access control system. Authentication information is transmitted to an electronic locking device configured to restrict access to an entry point of the access control system. A smart device comprises a light-emitting diode (LED) and a wireless networking radio for exchanging access control information with a remote server. The smart device may receive information from the remote server that configures the LED to present authentication information as an optical signal. The electronic locking device may comprise a photodetector arranged to receive the optical signal. According to various embodiments, the smart device may comprise a user interface display. Presentation of the authentication information may include rendering a webpage comprising a dynamic visual feature that changes visual content appearing on the user interface display so as to convey the authentication information as the optical signal emitted by the user interface display.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/289,116, entitled “VISIBLE LIGHT COMMUNICATION OF AN ACCESSCREDENTIAL IN AN ACCESS CONTROL SYSTEM” and filed on Oct. 7, 2016, nowallowed, which claims the benefit of U.S. Provisional Patent ApplicationNo. 62/239,884, entitled “APPARATUS AND METHOD FOR MULTI-CHANNELCOMMUNICATION IN AN ACCESS CONTROL SYSTEM” and filed on Oct. 10, 2015,each of which are incorporated herein by reference in their entirety.

TECHNICAL FIELD

This disclosure relates generally to the field of electronic accesscontrol, and more particularly to the use of visible light communicationsignals to exchange information between electronic devices in an accesscontrol system.

BACKGROUND INFORMATION

Electronic access control systems typically provide the means toexchange access control information between electronic devices. By wayof example, an electronic key or other electronic access control devicemay transmit, via wired or wireless communication technologies,authentication information such as an access code to an electronic lockin order to initiate an unlocking event.

In many access control systems, existing communication techniques sufferfrom disadvantages that may make the exchange of desired informationimpractical. For instance, if the time period required to transmit orexchange access control information is perceptible to users, it cansubstantially reduce the utility of the system. In a facility whereinstantaneous access to an area or item is desired, time delaysassociated with electronic communications or configuration of devicesfor communication may be intolerable. Moreover, it has becomecommonplace in the broad field of electronic access control to energizedevices with replaceable or rechargeable power sources, such asbatteries. Frequent exchange of information between devices can quicklydrain the capacity of depletable power sources, rendering the systeminoperative.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of this disclosure, non-limiting andnon-exhaustive embodiments and implementations of the disclosure aredescribed, including various embodiments and implementations withreference to the accompanying drawings, in which:

FIG. 1 is a block diagram illustrating an example electronic lockingdevice.

FIG. 2 is an exploded perspective view illustrating an exampleelectronic locking device, wherein elements of the electronic lockingdevice are arranged in a knob-like housing.

FIG. 3A is a partly exploded perspective view illustrating the exampleelectronic locking device of FIG. 2 as assembled and furtherillustrating an example mortise shell, wherein the example mortise shellis shown exploded.

FIG. 3B is a perspective view illustrating the example electroniclocking device of FIG. 2 coupled to the example mortise shell of FIG.3A.

FIG. 4 is a block diagram illustrating example communications between anoptical signal generator and an electronic locking device and examplecommunications between the optical signal generator and an accesscontrol server.

FIG. 5 is a perspective view illustrating a user positioning an opticalsignal generator comprising a display screen to facilitate delivery ofan optical signal presented on the screen to an electronic lockingdevice.

FIG. 6 is a block diagram illustrating example communication interfacesbetween communication circuitry of an administration badge andcommunication circuitry of an electronic locking device.

FIG. 7A is a block diagram illustrating example communications betweenan administration badge and an electronic locking device.

FIG. 7B is a block diagram illustrating example communications betweenan administration badge and a system monitor and example communicationsbetween the system monitor and an access control server.

FIG. 8 is a flowchart illustrating an example method of establishing abidirectional communication interface between an administration badgeand an electronic locking device.

FIG. 9 is a flowchart illustrating an example method of initiating anaccess event at an electronic locking device by transmitting opticalcommunication signals from an optical signal generator to the electroniclocking device.

FIG. 10 is a flowchart illustrating an example method of initiating anaccess event at an electronic locking device with an optical signalgenerator, wherein the optical signal generator obtains authenticationinformation from an access control server located away from the opticalsignal generator.

FIG. 11 is a block diagram illustrating example wireless communicationsbetween an electronic locking device, an optical signal generator, anadministration badge, and an access control server, and furtherillustrating example communications between the access control serverand a financial institution located remotely from the access controlsystem.

FIG. 12 is a flowchart illustrating an example method of automaticallycalculating a monetary fee and charging said fee to a user of an accesscontrol system, the monetary fee being calculated based, at least inpart, on access control information associated with transmission ofoptical signals to an electronic locking device.

FIG. 13 is a rendering of an optical signal generator comprising adisplay screen illustrating an example graphical user interface whereinaccess control information associated with a user login is displayed onthe screen.

FIG. 14 is a rendering of an optical signal generator comprising adisplay screen illustrating an example graphical user interface whereinaccess control information associated with a user is displayed on thescreen.

FIG. 15 is a rendering of an optical signal generator comprising adisplay screen illustrating an example graphical user interface whereinauthentication information associated with an electronic locking deviceis presented as a dynamic image displayed on the screen.

FIG. 16 is a rendering of an optical signal generator comprising adisplay screen illustrating an example graphical user interface whereinaccess control information associated with an electronic locking deviceis displayed on the screen.

FIG. 17 is a rendering of a smart device comprising a display screenillustrating an example graphical user interface wherein access controlinformation associated with locking devices assigned to a user isdisplayed on the screen.

FIG. 18 is a rendering of an optical signal generator comprising adisplay screen illustrating an example graphical user interface whereinaccess control information associated with a user's current accesspermissions is displayed on the screen.

FIG. 19 is a rendering of an optical signal generator comprising adisplay screen illustrating an example graphical user interface whereinaccess control information associated with an electronic locking deviceis displayed on the screen.

FIG. 20 is a rendering of an optical signal generator comprising adisplay screen illustrating an example graphical user interface whereinaccess control information associated with an electronic locking deviceis included in a short message service text message displayed on thescreen.

FIG. 21 is a rendering of an optical signal generator comprising adisplay screen illustrating an example graphical user interface whereinauthentication information associated with an electronic locking deviceis presented as a static image displayed on the screen.

FIG. 22 is a rendering of an optical signal generator comprising adisplay screen illustrating an example graphical user interface whereinaccess control information associated with locking devices assigned to auser is displayed on the screen.

FIG. 23 is a rendering of an optical signal generator comprising adisplay screen illustrating an example graphical user interface whereinaccess control information associated with locking devices assigned to auser is displayed on the screen.

DETAILED DESCRIPTION

In view of the difficulties associated with transmitting diversecategories of access control information between electronic devices ofan access control system, the present inventor recognized there is aneed for providing a plurality of communication channels such thataccess control information of varying types may be transmitted viadistinct communication interfaces according to its type or intended use.Namely, the present inventor recognized that there is a need to transmitcertain types of access control information, such as authenticationinformation, via a unidirectional communication channel that does notrequire time consuming configuration, while other types of accesscontrol information, such as audit trail information, may be transmittedvia bidirectional communication channels that can be unreliable orrequire timely configuration of the devices prior to transmission.

To illustrate, the design of an access control system may demand thataccess control information of a certain type, or category, istransmitted with more urgency than other categories of access controlinformation employed by the system. In some systems, certain categoriesof access control information must be exchanged quickly and reliably forthe system to provide basic functionality to users. Meanwhile, othercategories of access control information may be peripheral, or thesystem may be designed such that immediate exchange of such informationis not necessary for effective operation. For example, the desiredmobility of personnel in an access control system may dictateinstantaneous, or near instantaneous, exchange of access controlinformation associated with access authentication, such as a password orID number. An electronic locking device capable of selectivelyrestricting access to an area or enclosure can exchange authenticationinformation with an electronic access device, such as an electronic keyoperated by a user of the system, in order to grant or deny the useraccess to the area or enclosure. Delays or interruptions in the exchangeof authentication information between lock and key may impede the user'smovement. In facilities where it is desired or necessary to have userspass quickly between restricted areas, or between unrestricted andrestricted areas, delays in the exchange of authentication informationcan render an access control system unusable.

Access control information of other types may be used by the system, orby users of the system, in a manner that renders instantaneous exchangesuperfluous. For instance, while exchange of access control informationassociated with user movement patterns may provide utility toadministrators of a system, instantaneous exchange of such informationmay not necessarily provide added benefit when compared to slowermethods of transmission, or delayed transmission. In some instances,administrators may use or analyze this information at the end of theday, or at the close of a week. In other facilities, such informationmay be used in the event of an emergency, or other rare or unusualevent. In these few examples, instantaneous exchange of user movementpattern information is unnecessary and could even impose delays on theexchange of more time-sensitive information, such as authenticationinformation. Further, exchange of certain voluminous categories ofaccess control information, such as information associated with previousaccess events (e.g. information relating to all successful openings of acertain locking device during the previous month), may demandsignificant time and electrical power. In some access control systems,transmission of voluminous categories of access control information mayeven be discouraged. For instance, in systems with high-traffic accesspoints, delays associated with exchange of voluminous information candecrease the overall utility of the system.

In access control systems designed to track and record the movement orusage of numerous devices and/or users, a high-bandwidth, bidirectionalwireless communication interface (e.g. Wi-Fi) can be used to facilitatethe exchange of sizeable volumes of information between devices.However, many high-bandwidth communication protocols require acommunicating device to first provide access credentials (e.g. Wi-Finetwork password), resulting in additional time to configure the devicefor communications. The need to configure a device, for example byproviding network and password information, to enable communicationsover certain communication protocols is not conducive to systemsdesigned to serve transient or one-time users. Further, manyhigh-bandwidth communication protocols, such as Wi-Fi, require dedicatedor specialized hardware to provide the communication networkinfrastructure. This may not be practical in sprawling or remotefacilities.

With other bidirectional wireless communication protocols, for examplethose that facilitate direct device-to-device communication,establishing a link between devices (i.e. “pairing”) may requireconsiderable time and/or be prone to failure or interruption. Forexample, in some systems utilizing Bluetooth communication protocols,establishing a communication link between devices can take up to 10seconds, or more. Depending on the desired operational thresholds of thesystem, this delay can be impractical. For instance, in various accesscontrol systems it is desired to provide users with near-instantaneousaccess to an entryway secured by an electronic locking device. In yetother systems, a delay in the opening procedure can cause unacceptablefrustration in users of the system, such as where an access controldevice is installed on a home residence or hotel door. Manybidirectional communication protocols, such as Bluetooth, typicallynecessitate a dedicated software application to be installed on thecommunicating device to manage the selection and exchange of desiredinformation. Finding and launching dedicated software applications, forexample on a commercially available smartphone or tablet computer, mayfurther increase the time required to establish a communication link andexchange information. Present bidirectional wireless communicationprotocols require the devices to include dedicated communicationcircuitry. Further, commercially available devices, such as smartphones,require the user to invest additional time to configure the device toenable the desired bidirectional communication, for example by enteringnetwork information or by configuring a software application executingon the smartphone. The present inventor recognized that dedicatedcommunication circuitry and time delays associated with configuration ofpresent bidirectional wireless communication protocols are not conduciveto exchanging authentication information; namely, in access controlsystems that accommodate transient or one-time users who may wish toutilize devices without the appropriate communication circuitry or whodo not desire to invest time reconfiguring their device for a one-timeuse.

The power consumption of high-bandwidth, bidirectional (i.e. half-duplexor full-duplex) communication interfaces can be prohibitive,particularly in access control systems employing electronic devicespowered by batteries (or similar depletable power sources). In suchsystems, exchanging authentication information (e.g. each time a userwishes to gain access to an area or item) via high-bandwidthcommunication protocols, such as Wi-Fi, will quickly exhaust the powersupply of an electronic locking device, rendering the systeminoperative. Indeed, in systems with depletable power sources,low-bandwidth communication interfaces (e.g. infrared, ZigBee, etc.) canoften be employed to conserve the limited supply of power. However, insystems utilizing low-bandwidth communication interfaces, the exchangeof certain categories of access control information is often restrictedby slow data transfer rates, thereby eliminating a systemadministrator's ability to monitor all elements of the system. Withexisting methods and technologies for transmitting or exchanging accesscontrol information in an access control system, administrators mustmake a choice between using high-bandwidth communication interfaces thatnecessitate an ample supply of electrical power and may entailconfiguration challenges and protracted or unreliable communicationbetween devices, or using low-bandwidth communication interfaces withsluggish data transfer rates that can hinder administrative monitoringand system functionality.

The present inventor recognized that responsiveness and powerconsumption of access control systems are both improved by distributingthe transmission of access control information across multiple, distinctcommunication channels depending, in part, on the characteristics of theaccess control information to be transmitted. In some instances, accesscontrol information can be transmitted via unidirectional (i.e. simplex)communication channels. For instance, the present inventor recognizedthat transmitting certain access control information via unidirectionalcommunication channels can result in a more flexible, responsive, andreliable access control system, namely in access control systems thataccommodate transient or one-time users.

Turning now to FIG. 1, an electronic locking device 100 comprises aprinted circuit board (PCB) 110, a power supply 140, and an electricmotor 150. The arrangement of electronic locking device 100 as shown inFIG. 1 is illustrative in nature and skilled persons will appreciatethat a variety of mechanical and electronic arrangements for electroniclocking devices are known in the field of electronic access control.Electronic locking device 100 can be arranged in any suitable mannerthat renders it capable of restricting access to an area, enclosure, oritem, or portion thereof. Generally speaking, electronic locking devicesknown to skilled persons typically comprise electronic circuitry forreceiving an input signal, a blocking member (or other mechanical meansfor restricting movement or operation of the locking device), and amotor, solenoid, or similar electrical device for actuating movement ofthe blocking member upon receipt of an authorized input signal. Theseelements are described to illustrate known implementations of electroniclocking devices and are in no way intended to limit the scope of thisdisclosure and the various embodiments and implementations of electroniclocking device 100 described herein.

Electric motor 150 in FIG. 1 can be operatively coupled to anyappropriate blocking member (not shown in FIG. 1). The form andarrangement of the blocking member may vary to suit the area or itemthat electronic locking device 100 is designed or intended to secure.Electric motor 150 can be operatively coupled to a blocking member (orany structural component capable of restricting access to the area,enclosure, or item) in any appropriate manner that enables therotational force generated by electric motor 150 to cause displacementof the blocking member from its default locking position; therebyallowing a user to operate electronic locking device 100, or tootherwise access the area, enclosure, or item secured by the device.Although electric motor 150 is illustrated in this disclosure as beingarranged within the same device or enclosure as the other components ofelectronic locking device 100, skilled persons will appreciate thatelectric motor 150 can, in accordance with various implementations, bearranged independently from the other components of electronic lockingdevice 100, for example on the other side of a door or enclosure.Although various embodiments and implementations described in thisdisclosure make reference to a motor device (i.e. electric motor 150),skilled persons will understand that a motor is but one example of adevice capable of actuating a blocking member and that other knowndevices and methods may have utility in certain embodiments. Forinstance, a solenoid device can be used to convert electrical power intoa mechanical force to actuate a blocking member. In otherimplementations, an electric switch can be utilized to restrict accessto an area or an item. For example, actuation of the switch may causedelivery of electrical power to a magnetic locking device, or to alighting device to illuminate an area that, without a light source,would be unusable or inaccessible. It will be understood that theembodiments and implementations described in this disclosure may haveutility in a variety of applications, namely those applicationsutilizing an authentication process to grant or restrict access to anarea or item, such as athletic clubs, rental cars, sporting events,parking garages, and vending machines, to identify just a few examples.

Referring still to FIG. 1, PCB 110 has embedded thereon, amicroprocessor 112 that is operatively associated with a plurality ofcomponents using wired links, wireless links, or a combination thereof.Skilled persons will appreciate that the term “microprocessor” is usedfor convenience and that microprocessor 112 may be implemented as anyappropriate electrical circuitry. Various embodiments described in thisdisclosure may be implemented using electrical circuitry. The term“electrical circuitry” includes hardware elements, software elements,and/or a combination of both hardware elements and software elements.Examples of hardware elements may include processors, microprocessors,circuits, circuit elements (e.g. transistors, resistors, capacitors,inductors, and the like), integrated circuits, application specificintegrated circuits (ASIC), programmable logic devices (PLD), digitalsignal processors (DSP), field programmable gate array (FPGA), logicgates, registers, semiconductor device, chips, microchips, chip sets,and so forth. Examples of software may include software components,programs, applications, computer programs, application programs, systemprograms, machine programs, operating system software, middleware,firmware, software modules, routines, subroutines, functions, methods,procedures, software interfaces, application program interfaces (API),instruction sets, computing code, computer code, code segments, computercode segments, words, values, symbols, or any combination thereof. Insome embodiments, hardware elements may execute software elements toprovide at least some of the described functionality.

Microprocessor 112, as illustrated by FIG. 1, can be operatively linkedto a wireless communication module 120 and a photodetector 130.Additionally, FIG. 1 shows PCB 110 as having embedded thereon, andoperatively linked to microprocessor 112, an accelerometer 134, and abeeper 136. Other components may be embedded on PCB 110 as desired,depending on the characteristics of the particular access controlsystem. For instance, PCB 110 can also include a light-emitting diode(LED) or similar device capable of delivering visual signals to a userof the device. Microprocessor 112 can include additional non-volatilememory 114 and a clock 116 embedded thereon. Electronic locking device100 can include additional electronic memory sites if desired andindeed, an example arrangement of PCB 110 is depicted in FIG. 1 ascomprising a separate flash memory 118 operatively associated withmicroprocessor 112.

Wireless communication module 120 is shown in FIG. 1 as comprising anembedded transceiver 122, but it will be understood that a transceiveror antenna can be provided in non-embedded configurations andoperatively linked thereto. It will further be understood thatelectronic locking device 100 may comprise a plurality of wirelesscommunication modules, for example to facilitate wireless communicationacross multiple protocols. Wireless communication module 120 may utilizevarious known methods and protocols of wireless communication includinginfrared, IEEE 802.11x, WI-FI DIRECT®, BLUETOOTH®, ZIGBEE®, NFC, and/orother wireless communication methods and protocols known to skilledpersons. Appropriate wireless communication modules can be obtainedcommercially and include that sold under the model number “MRF24WBOMA”by Microchip Technology of Chandler, Ariz. It will be appreciated byskilled persons that other suitable wireless communication circuitry mayhave utility in electronic locking device 100.

Photodetector 130 can be any optoelectronic device capable of receivingand converting light signals into electrical current, includingphotodetectors, photodiodes, phototransistors, etc. Use of the term“photodetector” is not intended to restrict any embodiments of thisdisclosure to a particular type or category of optoelectronic device.For example, photodetector 130 may be an imager, such as an activepixel-sensor (APS) imager incorporating a plurality of charge-coupleddevice (CCD) image sensors or complementary metal-oxide-semiconductor(CMOS) image sensors. In other applications, photodetector 130 maysimply be implemented as a light sensitive cell that measuresilluminance (lux) or irradiance values. Appropriate photodetectors arecommercially available and include the phototransistor photodetectorsold under the model number “KDT00030” by Fairchild Semiconductor of SanJose, Calif. The KDT00030 phototransistor photodetector, for example,has a maximum relative sensitivity to optical signals at wavelengths of630 nm (i.e. in the visible light range). However, it will be understoodthat other photodetectors with varying peak sensitivities may haveutility, for example photodetectors with peak sensitivities towavelengths above 800 nm can be used to receive infrared opticalsignals. Skilled persons will appreciate that other photodetectors notexpressly described herein may have utility in electronic locking device100. For example, in applications where photodetector 130 may be exposedto significant noise, an optoelectronic device comprising both aphotodetector and an amplifier can be employed to reduce noiseinterference.

In addition to non-volatile memory 114 embedded on microprocessor 112,flash memory 118 of PCB 110 can be commercially available flash memoryand, according to at least some embodiments, is configured to storeaccess control information, for example an audit trail (i.e. log ofprevious access events, such as details associated with an opening ofelectronic locking device 100), access credential (e.g. access codes orother authentication information, etc.), and other access controlinformation used in the various embodiments and implementations of thisdisclosure. Skilled persons will appreciate that, for purposes of thisdisclosure, the term “access control information” refers to anyinformation stored, transmitted, or utilized by electronic lockingdevice 100, or by other electronic devices deployed in the accesscontrol system. While electronic locking device 100 is described andillustrated herein as containing a plurality of separate memory units(non-volatile memory 114, embedded on microprocessor 112, and flashmemory 118), it will be understood that electronic locking device 100may utilize any appropriate arrangement of electronic memory sites tostore information, including a single non-volatile memory unitoperatively linked to microprocessor 112.

Accelerometer 134 can be any device capable of measuring accelerationforces and may for example comprise a multi-axis accelerometer or,alternatively, acceleration forces can be measured by a combination ofmultiple, single-axis accelerometers. Beeper 136 can be any audiosignaling device such as a piezoelectric buzzer or other audio signalingdevices known to skilled persons. Although FIG. 1 depicts the variouscomponents as embedded on PCB 110 and linked to microprocessor 112,skilled persons will appreciate that in at least some implementations,these components can be arranged separately from PCB 110 and operativelyassociated with microprocessor 112 utilizing known methods such as wiredor wireless links, or a combination thereof.

Referring still to FIG. 1, it will be understood that wirelesscommunication module 120 is configured in a manner that renders itcapable of establishing a bidirectional wireless communication (BWC)interface 104 with a remote electronic device. BWC interface 104 can beimplemented using known wireless communication methods and protocols,and depending on the particular communication circuitry employed bywireless communication module 120, may include Infrared Data Association(IrDA), 802.11x, Wi-Fi Direct, Bluetooth, Zigbee, NFC, Z-WAVE®, DECT,RUBEE® and/or other wireless communication protocols known to skilledpersons.

Photodetector 130 is arranged, in relation to the other elements ofelectronic locking device 100, in a manner that renders it capable ofreceiving a wireless optical signal 102 from a remote source. Wirelessoptical signal 102 can be implemented using any optical communicationmethods and technologies known to skilled persons including visiblelight communication (VLC), infrared communication (IRC), and/orultraviolet communication (UVC). It will be appreciated that these termsrefer to the wavelength of the optical signal and that, for example,implementation of wireless optical signal 102 using VLC methods does notnecessarily mean that a human eye will be able to decipher theinformation carried by the signal.

Turning now to FIG. 2, in accordance with various embodiments,electronic locking device 100 comprises a knob-like housing configuredto secure or enclose at least some elements of electronic locking device100. The housing, or at least one element of electronic locking device100, can be operatively coupled to a modified lock cylinder or otherretaining mechanism (not shown in FIG. 2). FIG. 2 shows an explodedisometric view of the knob-like housing. In addition to PCB 110, powersupply 140, and electric motor 150, various implementations ofelectronic locking device 100 further comprise a retaining cap 200 and aknob body 216, thereby forming the knob-like housing. In accordance withsome implementations, electronic locking device 100 further comprises awindow 202, that may be retained against the circular opening in theanterior face of retaining cap 200. Window 202 is constructed of anymaterial that allows passage, through the window, of optical signalssuch that information carried by wireless optical signal 102 can bedelivered to photodetector 130. Here, retaining cap 200 may comprisesidewalls arranged such that window 202 is recessed slightly in relationto the anterior face of retaining cap 200. This arrangement (and similararrangements) of window 202 in relation to retaining cap 200 maysuppress ambient light from reaching photodetector 130 and causinginterference with wireless optical signal 102 (as will be describedfurther below with respect to FIG. 5).

As illustrated in FIG. 2, electronic locking device 100 furthercomprises a beeper pad 206 and a beeper vent 210 that, together withbeeper 136 (embedded on PCB 110 and not shown in FIG. 2), are configuredto generate audible signals. Electronic locking device 100 may compriseadditional elements such as a small O-ring 204, a lock screw 208, aspring 212, and a large O-ring 214, that are configured, in accordancewith various implementations, to couple retaining cap 200 to knob body216 and thereby secure the desired elements of the locking device insidethe knob-like housing. As depicted in FIG. 2, electronic locking device100 can, in some implementations, include a second printed circuitboard, locking PCB 218, located remotely from PCB 110. In suchimplementations, locking PCB 218 can be configured to control operationof electric motor 150. Here, locking PCB 218, like PCB 110, compriseselectrical circuitry (e.g. a microprocessor). In accordance with variousembodiments, locking PCB 218 is configured to cause delivery ofelectrical power to electric motor 150 upon receiving, via wired orwireless links, a signal from microprocessor 112 (embedded on PCB 110and not shown in FIG. 2) comprising instructions to lock or unlock theentry point. In this manner, criminal tampering or other unauthorizedforces that result in a compromise of PCB 110 may not also result in awrongdoer gaining access to or otherwise being able to manipulateelectric motor 150, thereby reducing the risk of unauthorized access tothe item or area secured by electronic locking device 100. The elementsshown in FIG. 2 illustrate but one possible implementation of electroniclocking device 100, arranged specifically for cooperation with a mortisecylinder. Skilled persons will appreciate that alternative arrangements,mechanical configurations, designs, and structural elements may haveutility in other implementations of electronic locking device 100. Forexample, electronic locking device 100 can be configured for cooperationwith, or as a replacement for, other locking hardware such as a padlock,cam lock, t-handle vending lock, or safe lock, just to name a fewpossible implementations.

Acknowledging that the configuration of electronic locking device 100may vary depending, at least in part, on the specifications of the areaor item to be secured, FIGS. 3A and 3B illustrate but one example ofelectronic locking device 100 configured for cooperation with a mortisecylinder. In this implementation, electronic locking device 100comprises a knob-like housing (such as that illustrated in FIG. 2). FIG.3A shows electronic locking device 100 operatively coupled to a mortiseshell 316 by way of stop plate 302, locking element 306, lock core 308,lock pin 312, and spring 314. Additionally, a snap ring 300, an O-ring304, an antenna 310, a dowel pin 318, a cam 320, and screws 322 can beutilized, at least in part, to couple electronic locking device 100 tomortise shell 316. Although electronic locking device 100 is describedand illustrated in this disclosure as being mechanically coupled to alock cylinder (here, a mortise cylinder), in various implementationselectronic locking device 100 and a lock cylinder or other lock hardwarecan be configured as a single locking device, such as a padlock. Inanother example, electric motor 150 can be configured remotely from theother elements of electronic locking device 100 and operatively coupledto a door or locking hardware, such as a deadbolt or other blockingmember designed to restrict access to an entry point. In yet anotherexample, electric motor 150 can be an element of an access controlsystem designed to restrict access to a large area (e.g. a turnstile atan arena or a barrier gate at a parking garage) or a small enclosure(e.g. an electronic locking system in an automobile or a gun safe).Here, the other elements of electronic locking device 100, namelyphotodetector 130 and microprocessor 112, can be configured to interfacewith or otherwise communicate unlocking or locking commands to an inputdevice for the access control system, such as a microprocessor or doorcontroller device that is designed to cause delivery of electrical powerto electric motor 150.

Persons of skill will appreciate that electronic locking device 100, inconjunction with cooperative lock hardware, can be configured tosimulate the mechanical operation of known, commercially availablelocking cylinders. Accordingly, mechanical and electronic operation ofthe example electronic locking device illustrated by FIG. 3A and FIG. 3Bwill only be described briefly as the operation of electronic lockcylinders is well understood by skilled persons. For instance, in adefault, locked position, spring 314 urges lock pin 312 away from lockcore 308 such that the distal end of lock pin 312 (i.e. the end of thelock pin extending outward from lock core 308) is positioned inside acavity or recess (not shown) of mortise shell 316, or otherwise contactsmortise shell 316 such that lock pin 312 can resist rotational movementof lock core 308 within mortise shell 316. In this example, lockingelement 306 is arranged at least partially inside of lock core 308 in amanner resisting movement, perpendicular to the longitudinal axis, oflock pin 312 (through the opening of lock core 308).

Here, electronic locking device 100 is configured to selectively enablerotational movement of lock core 308 within mortise shell 316 by causingrotation of locking element 306 such that the proximal end of lock pin312 (i.e. the end of the lock pin positioned at least partially insidelock core 308) is urged, by a rotational force acting on lock core 308,into the circular opening of the posterior end of locking element 306.For example, when a user presents valid authentication information toelectronic locking device 100, thereby initiating an unlocking sequence,microprocessor 112 (not shown in FIG. 3A) causes delivery of electricalpower to electric motor 150 (not shown in FIG. 3A) such that electricmotor 150 causes rotational movement of locking element 306. In thismanner, locking element 306 is rotated to an open position, wherein thecircular opening of locking element 306 is aligned with the circularopening of lock core 308. Thereafter, the user can manually apply forceto rotate electronic locking device 100 via the knob-like housing (i.e.rotate the housing by hand). Here, manual rotation of the housingapplies a rotational force to lock core 308 which thereby urges lock pin312 into the now aligned circular opening of locking element 306. Withlock pin 312 capable of displacement into the opening of locking element306 and no longer resisting rotational movement of lock core 308, thelocking device is in a mechanically openable state and the rotationalforce applied by the user causes rotation of lock core 308 which, inturn, rotates cam 320 to thereby actuate a latch or locking bolt (notshown in FIG. 3A) to unlock the entry point. Skilled persons willappreciate that FIGS. 3A and 3B illustrate but one implementation ofelectronic locking device 100 in cooperation with a lock cylinder andthat other arrangements may be appropriate depending on the item ordevice to be secured. For instance, in certain implementations,electronic locking device 100 comprises a single blocking member that,by itself, secures the entry point, for example by restricting movementof a door or enclosure. In such implementations, delivery of power toelectric motor 150 causes actuation of the single blocking member suchthat the door or enclosure (i.e. entry point) can be opened without anyfurther manipulation to the locking device.

Electronic locking device 100 may, in accordance with variousembodiments, have utility in a diverse range of applications.Accordingly, electronic locking device 100 can be arranged in a varietyof ways to secure different entry points. For convenience, the term“entry point” as used throughout this disclosure shall refer to anygateway facilitating access to an area, enclosure or item. An entrypoint may have, or may cooperate with, a blocking element restrictingaccess to the area, enclosure or item (e.g. a blocking member such as adeadbolt). The blocking element may be actuated to a state permittingaccess to the area, enclosure, or item, or portion thereof. While anentry point may, in an unlocked state, permit a user to physicallyaccess an area, enclosure, or item, such as a door or gate, it may alsoinclude access that is not necessarily physical in nature. For example,an entry point can comprise a window that, when unlocked, permits a userto view what is on the other side, but does not otherwise allow ingressand egress. To illustrate, entry points include doors, turnstiles,safes, gates, lockers, windows, cabinets, enclosures, parking garages,and vehicles, to identify just a few examples. Other specific examplesof entry points are identified in the various embodiments described inthis disclosure. As electronic locking device 100 can be arranged tointeract with a variety of blocking members and other hardware dependingon the design of the entry point to be secured, it will be understood byskilled persons that the phrase “unlock the entry point” refers to anyevent in which electronic locking device 100 (or a portion thereof) isactuated to permit access to an area, enclosure, or item. Descriptionsof various embodiments that include a reference to unlocking or openingof electronic locking device 100 are synonymous with unlocking the entrypoint, unless context dictates otherwise. To illustrate, in someimplementations electronic locking device 100 can be actuated todisplace a deadbolt to unlock an entry point such as a door. In otherimplementations, electronic locking device 100 can be actuated todisplace a lift gate to unlock an entry point such as a parking garage.

In accordance with various embodiments, electronic locking device 100 isconfigured to receive authentication information from an electronicdevice via wireless optical signals. Referring now to FIG. 4, electroniclocking device 100 is configured to restrict movement of and selectivelycontrol access to door 400. As illustrated in FIG. 4, in this exampleelectronic locking device 100 is coupled to and restricts rotationalmovement of door handle 402. A user wishing to operate electroniclocking device 100 (e.g. for the purpose of opening door 400) positionsoptical signal generator 404 such that wireless optical signal 102 canbe received by photodetector 130 (not shown in FIG. 4) of electroniclocking device 100. Optical signal generator 404 can be any electronicdevice capable of generating optical signals that can be received andconverted by photodetector 130, including, for example, a smart devicesuch as commercially available smartphones and tablets. As used in thisdisclosure, the term “smart device” refers to a network device that isgenerally connected to other devices or networks and can operate to someextent interactively and autonomously. Examples of smart devices includesmartphones (e.g. Apple iPhone, Android phones, etc.), tablets andphablets (e.g. Apple iPad, Amazon Kindle, Google Nexus, Samsung Noteetc.), smart watches (e.g. Apple Watch, Samsung Gear, etc.), personaldesktop computers, laptop computers, to identify a few specificelectronic devices.

In some implementations, optical signal generator 404 transmitsauthentication information, such as an access credential or access code,to electronic locking device 100 via wireless optical signal 102. Asused throughout this disclosure, the term “authentication information”refers to any information utilized by a component of an access controlsystem (e.g. electronic locking device 100) to authenticate a user ordevice, for example if authentication is desired prior to initiatingaccess, operation, or communication. Authentication information caninclude information such as access codes or other credentials (e.g.binary string), authorized time and date schedules (i.e. permissions toaccess certain electronic locking devices at certain times), user names,passwords, and ID numbers, to identify just a few specific examples.Authentication information is generally described in this disclosure ascomprising access codes, however skilled persons will appreciate thatthis is illustrative in nature and does not limit authenticationinformation to any particular content or arrangement. For clarity,authentication information is a subset of access control informationspecifically related to the authentication of a user or device.

As described above, wireless optical signal 102 can be implemented usingany known optical communication methods. For example, optical signalgenerator 404 can transmit authentication information to electroniclocking device 100 via visible light communication (VLC) methods andtechnologies. In at least some embodiments, optical signal generator 404is operatively associated with one or more light-emitting diodes (LEDs).The LED can be configured to generate visible light pulses at afrequency or pulse pattern capable of transmitting information, in theform of VLC signals, to electronic locking device 100. It will beunderstood that the term visible light does not necessarily mean thatthe pulses or other modulations of the optical communication will bevisible to the human eye. Rather, visible light communication is used torefer to the wavelength of light used to facilitate transmission ofinformation, with light in the visible spectrum generally falling,depending on the visual acuity of the viewer, anywhere betweenapproximately 375 and 780 nanometers (nm). In other embodiments, opticalsignal generator 404 comprises an infrared (IR) transmitting device tofacilitate transmission of information to electronic locking device 100using IrDA or other IR protocols. It will be appreciated by skilledpersons that VLC and IrDA are examples of appropriate opticalcommunication protocols and that other optical signals may be used toimplement wireless optical signal 102.

FIG. 5 illustrates a user positioning optical signal generator 404 suchthat wireless optical signal 102 can be delivered to photodetector 130(not shown in FIG. 5) in accordance with various embodiments of thisdisclosure. A specific entry point is not illustrated in FIG. 5; rather,skilled persons will appreciate that installation boundary 500represents any appropriate entry point arranged to cooperate with thisparticular implementation of electronic locking device 100. If opticalsignal generator 404 comprises a display screen such as that commonlyfound on commercially available smartphones or tablets, optical signalscan be generated via a light source associated with the display screen.The display screen can be any user interface display capable ofproducing visual content to the user, including an LED display, anorganic light-emitting diode (OLED) display, a liquid crystal display(LCD), and touchscreen embodiments thereof, just to identify a fewexamples. Here, a user positions optical signal generator 404 such thatlight signals generated by its display screen are directed towards theanterior face (i.e. the face extending outward from the door orenclosure) of electronic locking device 100. To illustrate, in thisorientation of optical signal generator 404, the display screen (orother optical transmitting device such as an LED) is directing VLCsignals towards window 202 of electronic locking device 100. In thisexample, electronic locking device 100 is configured in a mannerallowing wireless optical signal 102 to pass through window 202 and bereceived by photodetector 130 (not shown). In various embodiments, theuser may actually place at least a portion of the display screen (orother surface portion of optical signal generator 404) in contact withthe anterior face of electronic locking device 100. Here, the sidewallsof retaining cap 200 (discussed above with respect to FIG. 2) may, inconjunction with the surface of the display screen, block ambient lightthat could otherwise interfere with accurate reception of wirelessoptical signal 102 at photodetector 130. Skilled persons will appreciatethat the exact position of optical signal generator 404 in relation toelectronic locking device 100 may vary depending on the configuration ofthe locking device and the communication protocols utilized in theimplementation of wireless optical signal 102.

Turning now to FIGS. 1 & 4, electronic locking device 100 can beconfigured to compare (e.g. utilizing electrical circuitry such asmicroprocessor 112) authentication information transmitted by opticalsignal generator 404 with authentication information or other accesscontrol information stored in memory sites of electronic locking device100 (e.g. in non-volatile memory 114 or flash memory 118). For example,where authentication information is transmitted to electronic lockingdevice 100 via wireless optical signal 102, photodetector 130 mayconvert the received wireless optical signal 102 into a correspondingelectrical signal representing the authentication information. Here,photodetector 130 (or cooperative electrical circuitry) may perform ananalog-to-digital conversion, sampling the optical signal at definedintervals, to generate the corresponding electrical signal. It will beunderstood that photodetector 130 may convert or transform wirelessoptical signal 102 according to other known methods and techniques.

Skilled persons will appreciate that various methods and techniquesexist for authenticating users in an access control system. For example,in accordance with at least some embodiments, writing a list ofauthorized access codes into flash memory 118 will enable electroniclocking device 100 to accept authentication information from at leastone electronic access device, such as optical signal generator 404. Whenelectronic locking device 100 receives authentication information fromoptical signal generator 404, it is configured to compare the receivedauthentication information (in this example, an access code) with thelist of authorized access codes previously written to flash memory 118.If electronic locking device 100 determines that at least a portion ofreceived authentication information matches at least a portion of theauthentication information stored in flash memory 118, it can initializean unlocking sequence to unlock an entry point, for example by causingdelivery of power to electric motor 150 to actuate a blocking memberrestricting access to the entry point. It will be understood that acomparison of received authentication information with informationstored in memory is but one example of authenticating the user or deviceand that electronic locking device 100 can perform other operations todetermine whether the received authentication information corresponds toaccess control information stored in memory, or whether theauthentication information otherwise authorizes the user of thetransmitting device to access the entry point. If electronic lockingdevice 100 determines that the received authentication information doesnot authorize the user to access the entry point, it can alert the userthat access to the device is denied, for example by generating anaudible tone via beeper 136, or by generating other visual or audiblesignals. In some implementations, electronic locking device 100, uponreceipt of invalid or expired authentication information, transmits asignal to a remote device to indicate an unauthorized access attempt,such as optical signal generator 404, an alarm, or a server device.

Electronic locking device 100 can be configured to search through theentire list of authorized codes in flash memory 118 for comparison withreceived authentication information. In other implementations,electronic locking device 100 can use a pointer to select a single code,or a subset of the access codes in flash memory 118, for comparison withreceived authentication information. To demonstrate one example, ifelectronic locking device 100 is indeed configured to utilize a pointer,a set of access codes is written to flash memory 118. In suchimplementations, optical signal generator 404 or other suitableelectronic device capable of communicating access control information tooptical signal generator 404 can maintain, in memory sites, a copy ofthe same set of access codes that were written to flash memory 118 ofelectronic locking device 100. Thereafter, each time an access code istransmitted to electronic locking device 100, the pointer is advanced(in both memory sites of electronic locking device 100 and opticalsignal generator 404) such that previously used access codes are nottransmitted or otherwise not valid for use in future access events.

In accordance with some embodiments, multiple pointers can be utilizedby electronic locking device 100 in order to maintain operability with aplurality of electronic access devices. In various implementations, twoor more access devices are configured to transmit authenticationinformation to electronic locking device 100. For example, if severaloptical signal generators are deployed in an access control system, itmay be impractical to synchronize the pointer values in each opticalsignal generator 404, for example if the devices are not configured tofrequently exchange access control information with one another or witha management device, such as a system server. Accordingly, electroniclocking device 100 can maintain a separate pointer value for eachoptical signal generator 404 deployed in the system. In this example,two or more optical signal generators each have, in memory sitesthereof, a copy of an access code set (or other authenticationinformation). Here, each optical signal generator 404 can be associatedwith a unique pointer value whereby each signal generator will,according to its pointer value, transmit authentication information froma different location in the shared set of access codes. Authenticationinformation transmitted to electronic locking device 100 can compriseboth a device identification value (e.g. serial number of optical signalgenerator 404) and an access code. Electronic locking device 100, uponreceipt of the authentication information, uses the pointer associatedwith the transmitting device to select an access code stored in memoryfor comparison with the access code received from the transmittingdevice. Thereafter, electronic locking device 100 advances the pointerassociated with the transmitting device (in memory sites of the lockingdevice), rendering the received authentication information invalid foruse in future access events. Likewise, optical signal generator 404 canbe configured to advance a pointer value maintained in memory sites ofthe optical signal generator. In this manner, electronic locking device100 can maintain independent pointer values for each optical signalgenerator 404 deployed in the system, allowing a plurality of devices toutilize a single set of authentication information while reducing theneed to synchronize such information across devices. Skilled personswill appreciate that storing pointer values associated with a set ofinformation is but one example of maintaining authentication informationand that other techniques and methodologies may have utility dependingon the design of the system. For instance, electronic locking device 100can be configured such that it stores, in memory sites thereof, a codeor set of authentication information that is unique to each opticalsignal generator 404 deployed in the system.

Referring only to FIG. 4 now, in accordance with some embodiments,optical signal generator 404 can communicate with an access controlserver 460 located away from the signal generator to receiveauthentication information. For example, if optical signal generator 404is configured as a smartphone or other similar electronic device with awireless networking radio or other wireless communication circuitry, auser of optical signal generator 404 can use a web browser application(e.g. a conventional, commercially available mobile browser application)executing on the device to communicate with access control server 460.In this manner, a user seeking access to electronic locking device 100can retrieve authentication information from a remote server, forexample via BWC interface 104 and a communication network 450.Communication network 450 can be a wireless local area network (WLAN),for example if access control server 460 is configured to communicateacross the same WLAN or alternatively, if communication network 450 andaccess control server 460 are both connected to the Internet. Skilledpersons will appreciate that a WLAN refers to a wireless computernetwork that links two or more devices within a limited area, such as abuilding or school. A WLAN can be implemented using various wirelessnetworking protocols, including IEEE 802.11 (Wi-Fi) and other similarcommunication protocols operating in a frequency range typically between2.4 GHz and 5.9 GHz. Alternatively, communication network 450 can be awireless wide area network (WWAN), such as a cellular network wherebyoptical signal generator 404 connects to the Internet and retrievesauthentication information from access control server 460 using cellularcommunication technologies. Skilled persons will appreciate that a WWANrefers to a wireless network with broader coverage than a WLAN. A WWANcan be implemented using various wireless protocols including mobiletelecommunication cellular network technologies such as long-termevolution (LTE), global system for mobile communications (GSM), codedivision multiple access (CDMA), and the like. A WWAN can also beimplemented using wireless communication standards based on IEEE 802.16,such as worldwide interoperability for microwave access (WiMAX).Alternatively, a WWAN can be implemented by communicatively linking aplurality of short range communication nodes to create a mesh network.In yet other implementations, communication network 450 can be alow-power, wide-area network (LPWAN) whereby devices such as opticalsignal generator 404, electronic locking device 100, and access controlserver 460 may exchange information across long distances using lowerbit rates, for example as interconnected devices using technologies andcommunication protocols commonly associated with the “Internet ofThings.” Other communication networks and protocols known to skilledpersons may have utility in various implementations.

In accordance with at least some embodiments, access control server 460can operate as a remote administration system to control, monitor, orprovide information to other devices in the access control system.Access control server 460 can comprise memory sites including a databaseor list of access codes that is a copy of (or otherwise identical to) adatabase or list of access codes stored on electronic locking device100. A user of optical signal generator 404 can use a web browserapplication executing on optical signal generator 404 to request, fromaccess control server 460, authentication information for electroniclocking device 100. Depending on the desired security of the accesscontrol system, access control server 460 can be configured to requirethe user of optical signal generator 404 to authenticate his or heridentity prior to transmitting the requested access code, for example byentering in a user name and password or by utilizing other known methodsto authenticate the user. In some implementations, optical signalgenerator 404 transmits biometric information associated with the userto access control server 460 in order to authenticate the user.

As described elsewhere in this disclosure, electronic locking device 100can be configured to use a pointer when comparing receivedauthentication information such that electronic locking device 100compares received authentication information with a single access code,or subset of access codes, stored in flash memory 118. Access controlserver 460 can maintain information concerning the location of thepointer in electronic locking device 100 such that access control server460 provides the code (or a limited number of codes) stored in memory atthe location associated with the pointer. After electronic lockingdevice 100 receives valid authentication information from optical signalgenerator 404 and initiates an unlocking sequence, it can be configuredto advance the pointer in flash memory 118 such that authenticationinformation used in previous access events will no longer be valid foruse in future access events. Likewise, access control server 460 canalso advance the pointer associated with that particular electroniclocking device. In other implementations, electronic locking device 100and access control server 460 can be configured to advance the pointerafter a predetermined period of time has elapsed. In this manner,electronic locking device 100 and access control server 460 mayminimize, or even eliminate, the risk associated with surreptitiousinterception of authentication information transmitted by optical signalgenerator 404 during an access event.

In yet other implementations, access control server 460 randomizes thepointer value for electronic locking device 100. To illustrate,electronic locking device 100 can be configured such that it does notmaintain a pointer value associated with a set of stored access codes.Instead, electronic locking device 100 uses a pointer value transmittedby optical signal generator 404 during an access event. For instance,access control server 460 may maintain, in memory sites associatedtherewith, a set of access codes for use with electronic locking device100. The quantity of access codes operable with a particular lockingdevice may vary depending on the requirements and desired entropy of thesystem. In certain implementations, electronic locking device 100 can beconfigured with a set of access codes comprising one hundred values. Inother implementations, electronic locking device 100 can be configuredto accept access codes from a set comprising over one hundred thousandvalues. In yet other access control systems, each electronic lockingdevice deployed in the system can be configured for use with a uniqueset of access codes that is not valid for use with any other lockingdevice in the system. Skilled persons will appreciate that thedescription of access code sets herein is illustrative in nature anddoes not limit the scope of this disclosure to any particulararrangement or use of authentication information.

In accordance with at least some embodiments, optical signal generator404 can be configured to transmit, to electronic locking device 100 viawireless optical signal 102, information comprising an access code and apointer value associated with the access code. Access control server 460can generate a random or pseudo-random pointer value corresponding to aposition in the set of access codes. Access control server 460 utilizesthe random or pseudo-random pointer value to select an access code fromthe set of access codes for transmission to optical signal generator404. In various implementations, access control server 460 uses knownmethods and techniques of random number generation in selecting a randompointer value. For example, in some implementations, access controlserver 460 employs software code equivalent to a pseudo-random numbergenerator. In other instances, access control server 460 selects arandom pointer value using a true random number generator that employsinput from radioactive, atmospheric, or other physical phenomena. Itwill be understood that other known methods for generating a randomnumber may be utilized by access control server 460 to select a randompointer value.

In accordance with various implementations, access control server 460and electronic locking device 100 may each contain, in memory sitesthereof, an identical set of access codes comprising, for example, onehundred access code values. Access control server 460 is configured torandomly select a pointer value associated with the position of a singleaccess code within the set of one hundred access codes stored in memoryof the server. To illustrate, if access control server 460 randomlyselects a pointer value associated with (i.e. pointing to) the accesscode in the 25^(th) position of the set of the 100 values, accesscontrol server 460 can then transmit, to optical signal generator 404,the access code stored in the 25^(th) position along with the associatedpointer value. Thereafter, optical signal generator 404 transmits toelectronic locking device 100, via wireless optical signal 102, theaccess code along with its associated pointer value. In response,electronic locking device 100 can use the received pointer value toidentify an access code stored in memory sites of the locking device(here, the code in the 25^(th) position of the code set). If the accesscode transmitted by optical signal generator 404 matches thecorresponding access code stored in memory of electronic locking device100, an unlocking sequence is initiated. Skilled persons will appreciatethat the term “match” is used in this example to denote that thetransmitted access code is authorized to operate electronic lockingdevice 100 and that, depending on the desired level of security,electronic locking device 100 may perform a transformation on at leastone of the codes prior to comparison. In other examples, authenticationinformation is encrypted by access control server 460 and electroniclocking device 100 decrypts the transmitted access code before executinga comparison.

In at least some embodiments, access control server 460 and/orelectronic locking device 100 can disable, or otherwise prevent use of,an access code after the code is used by a device to initiate an accessevent (either successful or unsuccessful). For instance, upontransmitting an access code to optical signal generator 404, accesscontrol server 460 can delete the access code from memory sites,increment a pointer, or otherwise disable the access code such that itwill not be valid in future access events. Likewise, electronic lockingdevice 100 can delete or disable an access code, for example a codereceived from optical signal generator 404, immediately after an accessevent is completed. To illustrate, if access control server 460 and/orelectronic locking device 100 contain a set of access codes that aredisabled after use, a system administrator can reprogram or modify theserver and/or locking device once all access codes have been used anddisabled. The administrator can write into memory sites of the serverand locking device, a new set of access codes to replace the expiredset.

In various embodiments, access control server 460 and/or electroniclocking device 100 may temporarily disable an access code after anaccess event. To illustrate, access control server 460 can be configuredto temporarily disable a particular access code following transmissionof the access code to optical signal transmitter 404. Access controlserver 460 may use various known methods to disable the code, such asadvancing a pointer, associating a time stamp, setting a variable, etc.In some implementations, access control server 460 disables the accesscode for a predetermined time period, such as one month. In otherimplementations access control server 460 disables the access code untilall other access codes stored in memory sites of the server have beenused. For instance, access control server 460 may have stored, in memorysites thereof, a set of one hundred access codes. Access control server460 can be configured such that each code is disabled after use (e.g.after the code is transmitted to optical signal generator 404). Afterall access codes in the set have been used (and thereafter disabled),access control server 460 can be configured to enable all or several ofthe access codes for use in future access events. In someimplementations, access control server 460 is configured to limit reuseof access codes, for example the server can be configured such thataccess codes may be used no more than 3 times before a new set of accesscodes must be programmed into memory sites of access control server 460and/or electronic locking device 100.

In yet other implementations, access control server 460 can beconfigured to enable a set of access codes for use or reuse after apredetermined percentage of the access codes in memory have previouslybeen transmitted to optical signal generator 404 or otherwise used in anaccess event. To illustrate, in accordance with at least someembodiments, after 50% of the access codes stored in memory sites ofaccess control server 460 have been used and thereafter disabled, accesscontrol server 460 enables all access codes in memory (including codespreviously disabled) for use or reuse in future access events. Personsof skill will appreciate that the quantity of access codes or otherauthentication information stored in memory and the particularconditions for disabling and enabling or reusing authenticationinformation described in this disclosure are illustrative in nature anddo not limit other quantities or conditions from being employed in anaccess control system. For example, in certain access control systems, aset of access codes stored in memory sites of electronic locking device100 and access control server 460 may contain over one hundred thousandaccess code values.

In accordance with various embodiments, electronic locking device 100can store a record of unsuccessful access events (e.g. unauthorizedattempts to open) and/or successful access events in memory sites, suchas flash memory 118. For instance, when a user of optical signalgenerator 404 transmits authentication information via wireless opticalsignal 102, electronic locking device 100 can be configured to store arecord of the event, for example by logging the time of thetransmission, ID of the user (if transmitted), and informationindicating whether or not the user successfully opened electroniclocking device 100. Skilled persons will appreciate that informationassociated with access events is not the only information electroniclocking device 100 can record and that other information may haveutility in various access control systems. To illustrate one example,electronic locking device 100 can be configured to record informationassociated with movement of the device, such as a log of signalsgenerated by accelerometer 134. It may also be desired to maintainaccess control information in memory sites of access control server 460,such as a record of the requests for authentication information receivedat the server. For example, access control server 460 can store inmemory sites associated therewith, information indicating the time anddate that authentication information was requested, the identificationof the user or device requesting the information, whether authenticationinformation was transmitted to a remote device, and various other accesscontrol information as may be utilized by devices in the system.

In accordance with at least some embodiments, electronic locking device100 can be configured to operate in a low-power or economy mode, wherebypower consumption of various electronic components is reduced, forexample to conserve power supply 140. Accordingly, electronic lockingdevice 100 can be configured to operate in a default sleep mode whereinparticular electronic components (e.g. those energized by power supply140) consume zero or minimal power. Electronic locking device 100 can befurther configured to selectively enable electronic components inresponse to an optical signal detected by photodetector 130. Toillustrate, electronic components of electronic locking device 100 canbe enabled and disabled by utilizing a logic gate. For example, via achip select or slave select pin on a microcontroller or other electricalcircuitry operatively associated with the component, or via adisable/enable bit associated with the component. It will be appreciatedby skilled persons that any known method for selectivelydisabling/enabling electronic components can be utilized, such asfirmware or software configurations, electronic switches, or even amechanical switch. It will also be understood that optical signals arebut one example of input that can be utilized by electronic lockingdevice 100 to selectively enable components or otherwise exit alow-power mode. Other forms of input can be used as a wake-up signal,for example signals generated by accelerometer 136 that indicate thelock has been subjected to a particular force or pattern of forces.

In some embodiments, optical signal generator 404 can be configured tofirst transmit a wake-up signal (e.g. short pulse of a visible lightsignal or a start sequence comprising a specific pattern of visiblelight flashes) carried by wireless optical signal 102 prior totransmitting authentication information. In this example, microprocessor112 can be configured to exit a low-power, sleep mode in response tophotodetector 130 receiving a wake-up signal or other predefinedinformation. For example, in the low-power, sleep mode, electricalcircuitry (e.g. microprocessor 112) of electronic locking device 100 isconfigured to ignore or otherwise to not process optical signalsreceived at photodetector 130 unless a wake-up signal is first received.To illustrate, electrical circuitry can be configured such that it doesnot sample (e.g. for analog-to-digital conversion) the optical signalinput at photodetector 130 unless a wake-up signal is first received.Upon receipt of the wake-up signal, electrical circuitry can beconfigured to enter an event initiation state. The electrical circuitrycan be configured, in the event initiation state, to sample the opticalsignal for conversion to a corresponding electrical signal. The opticalsignal may be sampled for a predetermined period of time or, forinstance, until receipt of a second signal similar to the wake-upsignal. In other implementations, electrical circuitry may, in a lowpower consumption state, sample the optical signal but may be configuredsuch that it does not perform any additional processing (e.g. byforgoing attempts to compare the received information with accesscontrol information stored in memory sites). In this manner, electroniclocking device 100 can reduce energy consumption and conserve powersupply 140 by not needlessly processing optical signals that are notrelated to the communication of access control information. Toillustrate, electronic locking device 100 can be installed on an entrypoint that is located near an artificial light source, such as asecurity floodlight. The artificial light source may be positioned in amanner such that it inadvertently delivers optical signals tophotodetector 130. In implementations utilizing a wake-up signal, thewake-up signal can be defined to contain information that would nottypically be present in optical signals emitted by artificial lightsources designed to illuminate buildings or outdoor areas. In thismanner, electronic locking device 100 can be configured to ignore or tonot process the optical signals received from the artificial lightsource. In other implementations, microprocessor 112 can be configuredto enable various components of the locking device, such as wirelesscommunication module 120, upon photodetector 130 receiving a wake-upsignal.

In various embodiments, wireless optical signal 102 is implemented as aunidirectional communication channel, facilitating transmission ofinformation from optical signal generator 404 to electronic lockingdevice 100. Power consumption of electronic locking device 100 may bereduced significantly by limiting communication during unlocking/lockingaccess events to a unidirectional channel (i.e. from optical signalgenerator 404 to electronic locking device 100 via wireless opticalsignal 102). The present inventor recognized that transmittingauthentication information during access events via a unidirectionalcommunication channel can improve the responsiveness of the system byreducing or eliminating the occurrence of significant delays orinterruptions associated with configuring or establishing abidirectional communication interface, such as Bluetooth. Moreover,implementing wireless optical signal 102 as a unidirectionalcommunication channel can reduce the need for the communicating device(e.g. optical signal generator 404) to include specialized communicationcircuitry requiring additional configuration prior to transmission,thereby improving usability in access control systems that may be usedby transient or one-time users. To illustrate, in accordance withvarious embodiments of this disclosure, a unidirectional communicationchannel can be implemented using any component configured to generate alight signal, such as an LED or other light source associated with aconventional display screen, thereby permitting a user desiring totransmit authentication information to electronic locking device 100 toutilize a wide range of commercially available electronic devices.Moreover, use of a light source associated with the display screen maynot require the user to configure the device prior to transmission ofwireless optical signal 102, thereby saving time and reducing the riskof user error.

If wireless optical signal 102 is indeed configured as a unidirectionalcommunication channel, access control information can be retrieved ordownloaded from electronic locking device 100 using alternatecommunication channels or interfaces. Turning now to FIG. 6, in at leastsome embodiments, an administration badge 600 can be configured toexchange access control information with electronic locking device 100.Administration badge 600 can be any device capable of communicating withwireless communication module 120 such as a smart device, includingcommercially available smartphones, tablets, laptop computers, smartwatches, and other electronic devices comprising circuitry capable ofbidirectional wireless communication. As illustrated in FIG. 6,administration badge 600 comprises, in various implementations, anoptical transmitter 602, a microprocessor 604, and a wirelesscommunication module 606. Optical transmitter 602 can be any devicecapable of transmitting an optical signal such as an LED or IRtransceiver. Wireless communication module 606 can be any wirelesscommunication circuitry capable of communicating via various knownmethods and protocols of wireless communication including infrared, IEEE802.11x, Wi-Fi Direct, Bluetooth, Zigbee, NFC, and/or other wirelesscommunication methods and protocols known to skilled persons. Opticaltransmitter 602 and wireless communication module 606 can be implementedas a single communication device or, in other implementations, bearranged separately and each operatively associated with microprocessor604 via wired or wireless links. In at least some implementations,administration badge 600 may further comprise flash memory 608 and abeeper 610.

It will be understood that FIG. 6 is intended to illustrate thecommunication interface between administration badge 600 and electroniclocking device 100. Accordingly, other elements may not be depicted inFIG. 6, such as a source of electrical power. Skilled persons willappreciate that other modules and elements may have utility inadministration badge 600 and that the components depicted in FIG. 6 arefor illustration purposes only and not intended to limit the arrangementof administration badge 600 in any way. Although administration badge600 is described in this disclosure as being independent of opticalsignal generator 404, it will be understood by skilled persons thatoptical signal generator 404 and administration badge 600 can beimplemented as a single smart device. For instance, a smart device, suchas a commercially available smartphone, can be configured to operate asoptical signal generator 404 (e.g. configured to transmit authenticationinformation via a unidirectional optical communication signal) andadministration badge 600 (e.g. configured to exchange access controlinformation via a bidirectional communication interface). In otherimplementations, administration badge 600 can be configured tooperatively couple to optical signal generator 404, for example via aUSB or other electronic data port.

Bidirectional communication methods and technologies can be employed tofacilitate the exchange or retrieval of voluminous categories of accesscontrol information, such as audit trail information including recordsof all or a portion of the previous access events at the locking device.Skilled persons will understand that the term “audit trail” refers toany information associated with events that have occurred or areoccurring at a device, and may include information associated withprevious unlocking events, denied access events, low battery alerts,updated access permissions, and so forth. Here, this information can beretrieved separately from authentication information or other forms ofaccess control information. In other implementations, such as whereoptical signal generator 404 and administration badge 600 areimplemented as a single electronic smart device, access controlinformation such as audit trail information can be retrieved viabidirectional communication methods contemporaneously with transmissionof authentication information via unidirectional optical signals emittedby the same device. When retrieving certain information, a systemadministrator or user may value the high-bandwidth of certainbidirectional communication protocols over responsiveness andreliability of the system. To illustrate, if a user of the system simplydesires to gain access to a door or enclosure, the user may expect oreven demand that the access procedure be nearly instantaneous.Conversely, if a system administrator desires to retrieve access controlinformation from devices in the system, the administrator may expect theprocess to entail additional time, such as time associated withconfiguration of administration badge 600 to perform the desiredcommunication. Accordingly, delays associated with pairing devices orconfiguration processes necessary to establish a bidirectional wirelesscommunication interface may be tolerable during retrieval of voluminousaccess control information (e.g. audit trails) or maintenance, whereassuch delays may not be tolerable by a user wishing merely to access alocking device.

To illustrate further, a system administrator may desire to periodicallyretrieve access control information stored in memory sites (e.g. flashmemory 118) of electronic locking device 100, such as audit trailinformation associated with previous access events in order to reviewuser access details at the locking device. As illustrated in FIG. 6,transmission of wireless optical signal 102 can initiate or enableelectronic locking device 100 for communication, for example whereelectronic components of electronic locking device 100 are configured ina default sleep or low-power mode. Here, the signal to initiate (i.e.wake up) electronic locking device 100 can be an optical signalcomprising, for example, a particular pattern, frequency, intensity, orother signal characteristic that can be detected by photodetector 130.Administration badge 600 can be configured to generate wireless opticalsignal 102 (e.g. to wake up electronic locking device 100) in responseto an action or event. For example, in some implementationsadministration badge 600 is configured to periodically transmit wirelessoptical signal 102, such as transmitting recurring signals every second.In others, the badge is configured to transmit wireless optical signal102 in response to an action by the user or administrator, for instanceupon the user actuating a button or switch on administration badge 600.If photodetector 130 detects a signal from administration badge 600 viawireless optical signal 102, microprocessor 112 can be configured toactivate wireless communication module 120 and initiate establishment ofBWC interface 104. Skilled persons will appreciate that administrationbadge 600 and electronic locking device 100 can be configured toestablish BWC interface 104 without use of an optical or other wake-upsignal. For instance, the use of low-power or sleep modes for variouscomponents of electronic locking device 100 may have utility in certainimplementations but not in others.

Administration badge 600 can be configured to request access controlinformation from electronic locking device 100. In certainimplementations, administration badge 600 can, contemporaneously withexchange of information, write a time stamp into flash memory 608 (orinto memory sites of the locking device). Subsequently, administrationbadge 600 can be configured to request the access control informationthat was written to memory sites of electronic locking device 100 duringthe time elapsed since administration badge 600 last retrieved accesscontrol information from that device. In yet other implementations,administration badge 600 can prompt the administrator to select the timeperiod for which access control information is desired. Skilled personswill appreciate that administration badge 600 can be configured toretrieve information from electronic locking device 100 as desired, forexample administration badge 600 can be configured to request all of theaccess control information stored in memory sites of electronic lockingdevice 100. Administration badge 600 can be configured to generate aperceptible alert upon successful retrieval of access controlinformation, for example via beeper 610 or a similar device capable ofgenerating perceptible signals, such as visual or tactile signals.

In various embodiments, administration badge 600 can be configured totransmit access control information to electronic locking device 100 viaBWC interface 104. To illustrate, administration badge 600 can transmitauthentication information, such as access codes, to the locking device.Here, rather than transmitting access codes to initiate an access event,authentication information can be transmitted to electronic lockingdevice 100 to modify information stored in memory sites of electroniclocking device 100. To illustrate, random access codes or other forms ofauthentication information can be written into memory sites ofadministration badge 600 (e.g. using access control server 460). Uponestablishment of BWC interface 104, between administration badge 600 andelectronic locking device 100, administration badge 600 can beconfigured to transmit the authentication information to electroniclocking device 100. In some implementations, administration badge 600can transmit authentication information along with instructions toreplace previously used or expired access codes stored in memory sitesof the locking device, such as flash memory 118. In otherimplementations, administration badge 600 can transmit information toelectronic locking device 100 that includes instructions to open orunsecure the device at a specified time in the future (e.g. at 8:00 am,every weekday), irrespective of whether the locking device receivesauthentication information from a user at the specified time. Inresponse to receiving authentication information from administrationbadge 600, electronic locking device 100 can be configured to write theinformation (e.g. access codes) to memory sites, for example to replaceor supplement access codes already existing in memory of the lockingdevice. In this manner, the authentication information used to operateelectronic locking device 100 may be modified, for example ifauthentication information associated with the locking device iscompromised or exhausted. Skilled persons will appreciate thatadministration badge 600 can be configured to transmit other types ofaccess control information, for example access event records associatedwith other devices in the system, firmware updates, bug fixes, orinstructions to blacklist or otherwise revoke access permissions for auser or device, to identify just a few examples.

In accordance with at least some embodiments, access codes or otherauthentication information can be generated by the manufacturer of theaccess control system and provided to a system administrator or user ofthe system. In other embodiments, a system administrator or user of thesystem can generate access codes for use in the access control system,for example by employing a pseudo-random or true random numbergenerator. For instance, a system administrator can utilize physicalphenomena to generate truly random access codes for use in a particularaccess control system. As described elsewhere in this disclosure, accesscodes may comprise any appropriate information that is capable ofelectronic storage and transmission, for example binary data obtainedfrom an analog to digital converter that is operatively associated witha hardware random number generator.

Various methods and techniques of generating authentication informationcan be utilized. For instance, if the security requirements of theaccess control system demand the use of truly random access codes, or ifsuch randomness is desired by the administrator of the system, ahardware random number generator can be employed, using, as an inputsource, any appropriate physical phenomena. In some implementations itmay be desired to use a Geiger counter to measure radioactive decay. Inother implementations it may be desired to measure thermal noise oratmospheric noise. Skilled persons will appreciate that many alternativephysical phenomena and hardware can be employed, in tandem, to generatetruly random data. An analog to digital converter, for example, can beused to transform the signals generated by the hardware random numbergenerator into binary data. Access codes of appropriate bit-length(which can vary based on system design and desired level of security)can be formed based on at least a portion of the randomly generatedbinary data and transmitted to the appropriate devices according toknown methods and techniques described in this disclosure.

Referring to FIG. 7A, in accordance with at least some embodiments,administration badge 600 can be presented to electronic locking device100 to establish a communication link for transmission or exchange ofaccess control information. In this example, electronic locking device100 is operatively coupled to door 400 to selectively restrict openingof the door. Electronic locking device 100 can be configured to recordaccess event information associated with access to door 400, such as thetime and date of each opening or attempted opening of the door. Here,access event information can be retrieved from electronic locking device100 by establishing BWC interface 104 between communication circuitry ofadministration badge 600 and wireless communication module 120 ofelectronic locking device 100. In accordance with various embodimentswhere administration badge 600 is presented within a short distance toelectronic locking device 100, BWC interface 104 can be implemented as awireless personal area network (WPAN). Skilled persons will understandthat a WPAN can be implemented using a variety of short range wirelesscommunication technologies, including Bluetooth, IrDA, Z-Wave, ZigBee,and so forth. Using a low-bandwidth wireless communication protocol toimplement BWC interface 104, such as those specified by IrDA, may aid inminimizing power consumption of electronic locking device 100. Indeed,in accordance with some implementations, administration badge 600comprises communication circuitry (e.g. IR transceiver) capable oftransmitting and receiving information formatted according to IrDA orsimilar infrared-based protocols known to skilled persons. It will beappreciated that BWC interface 104 between administration badge 600 andelectronic locking device 100 may not necessarily be implemented in amanner that establishes a WPAN and can be implemented using any knownwireless communication protocol as desired, such as Bluetooth, Zigbee,NFC, Wi-Fi Direct, and others known to skilled persons.

Administration badge 600 can, for instance, request access controlinformation that was written to memory sites of electronic lockingdevice 100 after a specified date and time, or after a particular eventwas recorded by the locking device. To illustrate, upon establishing BWCinterface 104, administration badge 600 can be configured to transmit amessage to wireless communication module 120 (of electronic lockingdevice 100) that includes instructions to retrieve all access controlinformation written to memory sites of the locking device during theprevious seven days. Upon receipt of the message, wireless communicationmodule 120 can be configured to send the message to microprocessor 112which responds by returning, to wireless module 120 for transmission toadministration badge 600, all access control information written tomemory sites of electronic locking device 100 (e.g. flash memory 118) inthe seven-day period immediately preceding receipt of the message. Aftertransmission of the access control information by wireless module 120,electronic locking device 100 can be configured to return to a defaultsleep state in order to minimize power consumption.

In accordance with various embodiments, access control information canbe transmitted from administration badge 600 to another electronicdevice. For example, information can be transmitted to a separate deviceto display the information or to use the information in connection withadministration or maintenance of the system. Referring now to FIG. 7B,administration badge 600 can transmit access control information to asystem monitor 700. System monitor 700 can be a commercially availablecomputing device such as a laptop or desktop computer. Alternatively,system monitor 700 can be a smart device, such as a smartphone, tablet,or other electronic device capable of displaying information to thesystem administrator, for example on a display screen associated withthe device. In yet other implementations, administration badge 600 andsystem monitor 700 can be implemented as a single smart device, such asa smartphone or tablet. Administration badge 600 can be configured totransmit access control information to system monitor 700 via knownmethods and technologies. For instance, if administration badge 600includes a universal serial bus (USB) plug and system monitor 700includes at least one universal serial bus (USB) socket, administrationbadge 600 can transmit access control information to system monitor 700via the USB socket. Alternatively, administration badge 600 can transmitaccess control information to system monitor 700 using wirelesscommunication methods, for example via the wireless communicationcircuitry used by administration badge 600 to establish BWC interface104 with electronic locking device 100. Upon receipt of access controlinformation, system monitor 700 can be configured to display theinformation to a user or administrator, for example via a graphical userinterface on a display screen. In some implementations, system monitor700 can be configured to use at least a portion of the access controlinformation to update a system database or otherwise modify informationin memory sites associated with the access control system. In otherimplementations, system monitor 700 can be configured to transmit amessage to a remote device or initiate an alarm or other perceptiblesignal if the access control information received from administrationbadge 600 indicates that a particular event has occurred, for examplenumerous unauthorized access attempts at a certain entry point.

In accordance with at least some embodiments, system monitor 700 can beconfigured to transmit access control information to a remote device,such as access control server 460. For example, system monitor 700 canexchange information with access control server 460 using similar wiredor wireless methods and technologies as have been described elsewhere inthis disclosure. In some implementations, system monitor 700 isconfigured to transmit, to access control server 460, access controlinformation associated with each electronic locking device 100 in thesystem. To illustrate, administration badge 600 can be used to retrieveaccess control information from electronic locking devices andthereafter transmit the retrieved information to system monitor 700.System monitor 700 can be configured to automatically transmit theinformation received from administration badge 600 to access controlserver 460. In other implementations, system monitor 700 can beconfigured to transmit access control information to access controlserver 460 in response to a command or other action by the user oradministrator, or upon expiration of a specified time period.

Access control server 460 can use access control information from thevarious electronic locking devices in the system in order to synchronizeor merge the access control information between memory sites of theserver and memory sites of the locking devices. Skilled persons willappreciate that synchronization of access control information acrossmultiple devices can provide redundancy in an access control system,thereby improving reliability in the event of a device failure. In someimplementations, synchronization of information can be used tocompensate for inherent limitations in the communication methodsemployed by various devices, for example if certain devices employunidirectional communication channels. To illustrate, access controlserver 460 can record information associated with transmission of anaccess code to optical signal generator 404. However, for variousreasons, a user of optical signal generator 404 may ultimately elect notto transmit the access code to electronic locking device 100. In somesituations, the user may wish to simply test generation of wirelessoptical signal 102 without intending to position optical signalgenerator 404 for transmission to electronic locking device 100. Inother instances, the user of optical signal generator 404 may experiencetechnical difficulties upon receiving the access code from accesscontrol server 460 and elect to request a new access code without firstattempting to access electronic locking device 100. Here, if wirelessoptical signal 102 is implemented as a unidirectional communicationchannel it may not be practical for optical signal generator 404 toprovide feedback to access control server 460 regarding whetherauthentication information was successfully transmitted to a lockingdevice. However, access control information can later be retrieved fromelectronic locking device 100 when delays associated with the exchangeof information are not likely to impact the utility of the system. Bysynchronizing, or merging the information between access control server460 and electronic locking device 100, the system administrator canreceive a more comprehensive record of events in the access controlsystem. The system administrator can use the merged access controlinformation to make modifications to the system or to troubleshootsystem errors. For example, the system administrator may want tounderstand how often access codes are transmitted (from access controlserver 460) to a particular optical signal generator 404 and comparethat information with the number of successful or unsuccessful accessevents actually initiated by the same optical signal generator.

In accordance with various embodiments, electronic locking device 100can be configured to transmit, via wireless communication module 120,access control information to various electronic devices of the accesscontrol system. In some implementations, power consumption can beincreased to obtain frequent or even real-time exchange of informationconcerning the use or status of electronic locking device 100. Toillustrate, electronic locking device 100 can be configured such that itperiodically transmits, via wireless communication module 120, accesscontrol information regarding the status of the locking device (e.g.indicating whether the device is secured or unsecured). Wirelesscommunication module 120 can transmit access control information toaccess control server 460, or to another electronic device in the accesscontrol system. Depending on the arrangement of the access controlsystem and the proximity of electronic locking device 100 to accesscontrol server 460, this transmission can be facilitated usingcommunication network 450 (e.g. a WLAN, LPWAN, or WWAN such as acellular network). In other implementations, this can be accomplished bydirectly transmitting access control information from wirelesscommunication module 120 to compatible communication circuitry of accesscontrol server 460, for example via a WPAN using Bluetooth or otherwireless communication protocols.

Access control information concerning the status (e.g. secured orunsecured) of electronic locking device 100 may comprise informationgenerated by various electronic components of the locking device, suchas accelerometer 134. For instance, signals generated by accelerometer134 can be used to determine a position of the locking device. Toillustrate, if electronic locking device 100 is in an unsecured state,accelerometer 134 may generate signals that are not typically producedwhen the device is in a secured state. Signals generated byaccelerometer 134 can likewise indicate if the device (or a componentthereof) is in a nonfunctional or emergency state, such as after orduring unauthorized tampering. Electronic locking device 100 can beconfigured to modify a lock status variable or other information storedin memory sites of the device based, at least in part, on signalsgenerated by accelerometer 134. In some configurations, electroniclocking device 100 can be equipped with other hardware to detect theposition or orientation of elements of the locking device, such as anelectrical contact configured to generate a signal based on the positionof a blocking member. Skilled persons will understand that a variety ofcomponents and devices can be used to provide information regarding theposition or orientation of various elements of the locking device andthat the accelerometer and electrical contact described herein areillustrative in nature and are not intended to restrict inclusion ofother devices in various embodiments.

In assorted implementations, electronic locking device 100 can beconfigured to wake up for brief periods to listen for or act uponincoming messages or signals, for example from administration badge 600.Referring now to FIG. 8, an example method 800 for establishing acommunication link between electronic locking device 100 andadministration badge 600 will be described in accordance with at leastsome embodiments of this disclosure. The method 800 begins at step 802where microprocessor 112 disables wireless communication module 120 fora predetermined duration, such as 50 milliseconds (ms). Next, the methodproceeds to step 804 where microprocessor 112 enables wirelesscommunication module 120. In step 806, wireless communication module 120is configured to operate in listen mode or to otherwise detect incomingwireless signals (e.g. from administration badge 600) for apredetermined period of time, said predetermined period being shorterthan the disabled period in step 802. For example, depending on theparticular communication protocols employed by electronic locking device100 and administration badge 600, wireless communication module 120 canbe enabled for a period no greater than 50% of the disabled perioddescribed in step 802.

If wireless communication module 120 detects an incoming signal fromadministration badge 600 in step 806, the method proceeds to step 808where BWC interface 104 is established between communication circuitryof electronic locking device 100 and communication circuitry ofadministration badge 600. Otherwise, if wireless communication module120 does not detect an incoming signal from administration badge 600within the predetermined period of time in step 806, the method returnsto step 802 where wireless communication module 120 is again disabled.Skilled persons will appreciate that the length of the predeterminedperiods of time that wireless communication module 120 is disabled andenabled may depend, at least in part, on the wireless communicationprotocols utilized. The specific values described herein areillustrative in nature and other durations may have utility in variousembodiments of this disclosure.

Upon establishing BWC interface 104 in step 808, administration badge600 and electronic locking device 100 can be configured to exchangeinformation in step 810, including access control information such asaccess codes or information associated with prior access events writtento memory sites of the locking device. Upon completion of the desiredinformation exchange in step 810, the method may optionally return tostep 802, for example if further communication is anticipated. If it isindeed desired to return to step 802 upon completion of communication instep 810, the duration of the time periods in step 802 and step 806 canbe configured such that a low duty cycle for wireless communicationmodule 120 is achieved while still preserving responsiveness of wirelesscommunications and overall locking device functionality. For example, ifBWC interface 104 is implemented using IrDA communication protocols, thepredetermined period that wireless communication module 120 is disabledin step 802 may be short enough that any associated delay is notperceptible to users of the system (e.g. 50 ms). By achieving a low dutycycle for energy intensive electronic components, such as wirelesscommunication module 120, overall power consumption of electroniclocking device 100 is thereby reduced. Skilled persons will appreciatethat configuring electronic components, such as wireless communicationmodule 120, to operate in a low-power mode may not be appropriate inevery system. For instance, in accordance with some implementations itmay be desired for wireless communication module 120 to operate in alisten mode indefinitely, wherein microprocessor 112 is not configuredto periodically disable communication circuitry to conserve power supply140.

Similar methods and techniques may be used with respect to otherelectronic components in electronic locking device 100. Referring now toFIG. 9, an example method 900 for initiating an unlocking event ofelectronic locking device 100 will be illustrated in accordance with atleast some embodiments. The method 900 begins at step 902 wheremicroprocessor 112 disables photodetector 130 for a predeterminedduration, for example 50 ms. Next, the method proceeds to step 904 wheremicroprocessor 112 then enables or otherwise causes delivery ofincreased electrical power to photodetector 130. In step 906,photodetector 130 is configured to detect incoming optical signals froma remote source (such as optical signal generator 404) for apredetermined period of time, this enabled period being shorter than thedisabled period described in step 902. For example, photodetector 130may be enabled for a period no greater than 10% of the disabled perioddescribed in step 902. If photodetector 130 detects an optical signalfrom optical signal generator 404 during the time period described instep 906, the method proceeds to step 908 where optical signal generator404 transmits authentication information to electronic locking device100 via wireless optical signal 102. Skilled persons will appreciatethat an optical signal detected by photodetector 130 in step 906 mayindeed comprise authentication information and that detection (step 906)and transmission of authentication information (step 908) are describedas separate steps for clarity purposes only. Otherwise, if photodetector130 fails to detect an incoming signal from optical signal generator 404within the predetermined period of time in step 906, the method returnsto step 902 where photodetector 130 is again disabled. The length of thepredetermined periods of time that photodetector 130 is disabled andenabled may vary, depending for example on the type of optical signalsutilized (e.g. VLC versus IRC versus UVC), the desired power consumptionof electronic locking device 100, and the desired responsiveness of thedevice.

Upon receiving authentication information from optical signal generator404 in step 908, the method proceeds to step 910 where photodetector 130transmits the authentication information to microprocessor 112.Microprocessor 112 compares the received authentication information withauthentication information or other access control information stored inmemory sites (e.g. flash memory 118) of electronic locking device 100.If microprocessor 112 determines that the authentication informationreceived in step 908 authorizes the user to operate electronic lockingdevice 100, it may initiate an unlocking sequence in step 912, forexample by causing delivery of increased electrical power to electricmotor 150 to actuate a blocking member or other device restrictingaccess to the entry point. Conversely, if microprocessor 112 determinesthat the authentication information received in step 908 does notauthorize the user to access electronic locking device 100, the methodmay return to step 902 where photodetector 130 is again disabled (themethod can be repeated if desired, with photodetector 130 alternatingbetween sleep/listen states). Similar to the power cycling of wirelesscommunication module 120, achieving a low duty cycle for photodetector130 reduces power consumption of electronic locking device 100 whileretaining operational responsiveness of the locking device, for exampleduring access events. The period of time that photodetector 130 isdisabled may be such a short duration that it is not perceptible tohuman users of the system, and may appear instantaneous to users duringnormal operation. Skilled persons will appreciate that the methoddescribed in FIG. 9 is illustrative in nature and that in someimplementations it may be desired to configure photodetector 130 tooperate in a listen mode indefinitely to maximize responsiveness.

FIG. 10 illustrates an example method 1000 for operation of electroniclocking device 100 wherein optical signal generator 404 obtainsauthentication information from a remotely located electronic device inaccordance with various embodiments. The method 1000 begins at step 1002where a user of optical signal generator 404 initiates transmission ofan electronic message (e.g. HTTP message) to access control server 460,the message comprising a request for access control information. Skilledpersons will understand that reference to the access control informationmay not be explicit in the electronic request message, for example theelectronic message may include an HTTP GET instruction that requests awebpage or other web resource that is associated with access controlinformation. Here, optical signal generator 404 can transmit the requestmessage using known wireless communication protocols (e.g. wirelesscommunication via a WLAN, or via a WWAN such as a cellular datanetwork). In accordance with various embodiments, the user of opticalsignal generator 404 can direct a web browser application executing onoptical signal generator 404 to a particular web address associated withaccess control server 460. In this manner, optical signal generator 404may act as a client device in accessing access control server 460 inaccordance with known client-server principles. In some implementations,a user can enter a web address directly into the web browser, forexample if optical signal generator 404 comprises a keyboard or isotherwise capable of accepting touchscreen input via a touchscreendisplay. In other implementations, navigation to the appropriate webpagecan be accomplished using a link to the web address, for instance byselecting, from an email or other electronic message, a hyperlink with areference to the webpage.

Although example method 1000 is further described below as beingimplemented with a web browser application configured to retrieve accesscontrol information from a webpage hosted by access control server 460,it will be understood that other software applications and communicationmethods may have utility in various embodiments. For example, inaccordance with some embodiments, the user can employ a dedicated mobileapp software application executing on optical signal generator 404 thatis configured to exchange electronic messages (e.g. via the Internet orother communication network) with access control server 460. Forexample, if optical signal generator 404 is implemented as acommercially available smartphone with an Android-based operating systeminstalled thereon, the user can employ a dedicated native mobileapplication written, for instance, in Java and configured to exchangeelectronic messages related to access control information. If opticalsignal generator 404 is implemented as a smartphone having an iOS (i.e.Apple) operating system, the dedicated native mobile application can bewritten in Objective-C. Alternatively, the user can utilize a mobile webapplication. Here, the mobile web application can execute within a webbrowser application and can be written, for example, in JavaScript,Cascading Style Sheets (CSS), HyperText Markup Language (HTML), HTML5,or other similar languages. In yet other implementations, the user canemploy a hybrid mobile application that uses native code (e.g. Java orObjective-C) and web code (e.g. JavaScript, CSS, HTML, HTML5). Skilledpersons will appreciate that these are just a few examples of mobile appsoftware applications that can be used to configure optical signalgenerator 404 to exchange access control information with access controlserver 460 through a computer network or other communications link.

The content of the request message delivered to access control server460 in step 1002 may vary based on the desired security of the system.For instance, in some implementations, the request message comprisesinstructions for access control server 460 to transmit (or provide inthe webpage) authentication information for a particular electroniclocking device 100. In other implementations, the request messageadditionally comprises instructions to transmit information associatedwith a login process whereby the user of optical signal generator 404 isprompted to enter (e.g. via keyboard or touchscreen in communicationwith optical signal generator 404) identifying information associatedwith the user, such as a user name or user ID and password, prior toreceiving access control information from the server. In yet otherimplementations, access control server 460 can be configured toautomatically provide, upon receipt of a request message from a device,a webpage comprising a login or other authentication process.

Next, the method proceeds to step 1004 where access control server 460transmits to optical signal generator 404, or otherwise provides via thewebpage, authentication information that is responsive to the requestmessage. In accordance with various embodiments, access control server460 can transmit authentication information along with instructionscausing optical signal generator 404 to present the authenticationinformation as wireless optical signal 102 in step 1006, for example bycausing the light source of a display screen associated with opticalsignal generator 404 to emit visible light at a certain frequency,intensity, or other measurable characteristic. In other implementations,access control server 460 can provide a webpage for display in the webbrowser application executing on optical signal generator 404. Accesscontrol server 460 can configure the webpage to display an animation,video, or other dynamic image such that visible light signals emitted bythe display screen convey the requested authentication information orother access control information. In various embodiments, optical signalgenerator 404 can be configured to continue transmitting authenticationinformation via wireless optical signal 102 for a predetermined time, oruntil user action interrupts the transmission, for example by actuatinga button associated with optical signal generator 404 or by stopping orpausing execution of the web browser application.

In step 1008, the user positions optical signal generator 404 tofacilitate delivery of wireless optical signal 102 to photodetector 130of electronic locking device 100. Depending on the optical protocolsused in implementing wireless optical signal 102, the user can orient alight source associated with optical signal generator 404 (e.g. displayscreen, LED, etc.) in a position that enables optical signals generatedby the light source to be received at photodetector 130. To illustrate,the user can position optical signal generator 404 such that the lightsource is within 90 degrees of a line-of-sight between the light sourceand photodetector 130. In other implementations, the user may positionoptical signal generator 404 such that a surface of optical signalgenerator 404 is in contact with electronic locking device 100. However,the desired orientation of optical signal generator 404 may vary withthe design of the access control system and the communication protocolsused to implement wireless optical signal 102.

Photodetector 130 receives the authentication information via wirelessoptical signal 102 in step 1010 and converts the optical signal to acorresponding electrical signal (carrying the authenticationinformation) to provide to microprocessor 112. Next, in step 1012,microprocessor 112 compares the received authentication information withauthentication information, or with other access control information,stored in memory sites (e.g. flash memory 118) of electronic lockingdevice 100. If microprocessor 112 determines that receivedauthentication information corresponds to stored authenticationinformation in a manner authorizing access, it causes delivery ofincreased electrical power to electric motor 150 in step 1014, therebyactuating a blocking member to open or unlock the entry point. Skilledpersons will appreciate that comparing received authenticationinformation with authentication information stored in memory sites ofelectronic locking device 100 is but one method of authenticating accessand other known methods and techniques of authenticating access may haveutility in various embodiments. If received authentication informationdoes not authorize access in step 1012, the method may return to step1002 where the user can again request authentication information fromaccess control server 460, if desired. Skilled persons will furtherappreciate that electronic locking device 100 and optical signalgenerator 404 can be configured to alert the user if access isauthorized or denied. For instance, electronic locking device 100 canemit a visual signal via an LED or an audible signal via beeper 136.

Referring now to FIG. 11, access control server 460 can be configured toexchange information with electronic devices located remotely from theaccess control system. In FIG. 11, system boundary 1150 denotes aseparation between elements located within the access control system(depicted above system boundary 1150) and elements located remotely fromthe system (depicted below system boundary 1150). For example, deviceslocated remotely from the system may be in another building or evenanother city. To illustrate, electronic locking device 100 can beinstalled on door handle 402 (associated with door 400). Optical signalgenerator 404 and administration badge 600 can each be configured tocommunicate with electronic locking device 100, as described elsewherein this disclosure. Additionally, optical signal generator 404 andadministration badge 600 can each be configured to communicate withaccess control server 460, for instance via BWC interface 104 by way ofcommunication network 450 (e.g. WLAN or WWAN). In accordance withvarious embodiments, at least one of optical signal generator 404 andadministration badge 600 can communicate with access control server 460to transmit or exchange access control information. In this example,access control information may comprise information associated withaccess events involving at least one of electronic locking device 100,optical signal generator 404, and administration badge 600. Accesscontrol server 460 can also be configured to communicate with a remoteelectronic device. For example, if access control server 460 isconnected (via wired or wireless link) to Internet 1100, access controlserver 460 can be configured to communicate with a remote electronicdevice also connected to Internet 1100. In accordance with variousembodiments, access control server 460 can communicate with anelectronic device located at a financial institution 1102. It will beunderstood that financial institution 1102 can be any businessconducting financial transactions, such as a bank, credit union,e-commerce business such as PayPal®, or insurance company. In thisexample, access control server 460 can communicate with an electronicdevice (e.g. server) at financial institution 1102 to authorize anelectronic funds transfer (EFT) or other form of payment on behalf of acustomer or member of financial institution 1102.

In accordance with at least some embodiments, users of electroniclocking device 100 can be charged a monetary fee associated with use ofthe device, the amount of the fee being based, in part, on device usageinformation. In some implementations, device usage information iscalculated using access control information stored in memory sites of atleast one of electronic locking device 100, optical signal generator404, access control server 460, and administration badge 600. In thiscontext, the term usage information means information associated withoperation of, or communication with, electronic locking device 100, suchas the amount of time elapsed between openings, the time and date thatelectronic locking device 100 was first accessed by a particular user,or the number of openings in a predetermined period of time, to identifyjust a few examples. In some implementations, usage information is usedto determine a monetary fee associated with use of electronic lockingdevice 100. For instance, electronic locking device 100 can be arrangedto restrict access to an area or item. The owner of the area or item maywish to charge others for use of or access to the area or item. Accesscontrol information written to memory sites of electronic locking device100, optical signal generator 404, administration badge 600, and/oraccess control server 460 can be used to calculate a value or feeassociated with use of the locking device. Thereafter, a user of thesystem can be charged, based at least in part on the calculated value orfee, for use of or access to the area or item secured by electroniclocking device 100.

To illustrate, in some implementations it is desired to charge a userbased on the period of time that an item or area is accessible to theuser. The duration that an item or area is accessible can be calculatedusing information associated with access events, such as informationassociated with an unlocking event initiated by electronic lockingdevice 100 that is recorded in memory sites of electronic locking device100 or optical signal generator 404. A user wishing to operateelectronic locking device 100 to unlock an entry point and gain accessto an area or item can initiate transmission of authenticationinformation via wireless optical signal 102, for instance by utilizingoptical signal generator 404. Optical signal generator 404 can beconfigured to write, to memory sites, information associated withtransmission of wireless optical signal 102, such as the time and datethat the signal was transmitted. In this manner, optical signalgenerator 404 can create a record of the precise moment that the userattempted to operate electronic locking device 100 to unlock the entrypoint. Electronic locking device 100 can also record informationassociated with the access event, such as the time and date whenauthentication information was received via wireless optical signal 102,or the time and date when electronic locking device 100 was opened. Ifthe user of optical signal generator 404 successfully transmits validauthentication information to electronic locking device 100, the usercan thereafter operate the locking device to unlock the entry point andaccess the area or item.

In accordance with various embodiments, electronic locking device 100can be configured such that authentication information is utilized notonly to unlock the entry point, but also to lock or secure the entrypoint. In such implementations, once the user is finished accessing thearea or item secured by electronic locking device 100, the user againtransmits information to electronic locking device 100 via wirelessoptical signal 102. As with the unlocking procedure for electroniclocking device 100, optical signal generator 404 can be configured towrite, to memory sites, information associated with transmission ofauthentication information during the locking process, such as the timeand date that the signal was transmitted. In this manner, optical signalgenerator 404 can create a record of access events that includes, invarious implementations, the time and date that the user openedelectronic locking device 100 and the time and date thereafter that theuser secured electronic locking device 100. Accordingly, the durationduring which the user enjoyed access to the item or area secured byelectronic locking device 100 can be calculated using at least a portionof the information logged by optical signal generator 404. For instance,if access control information indicates that optical signal generator404 transmitted authentication information to unlock the entry point at10:00 am and subsequently transmitted authentication information to lockthe entry point at 12:00 pm, the user of the device may be charged fortwo hours of access to the item or area. In this example, if the owneror administrator establishes a fee of $25.00 per each hour of use, theuser of the item or area can be assessed a $50.00 fee for the two hoursof use.

In accordance with various embodiments, access control server 460 can beconfigured to automatically charge a user of electronic locking device100 based, at least in part, on access control information, such as timeand date information associated with access events. To illustrate,optical signal generator 404 can be configured to transmit, via BWCinterface 104, access control information to access control server 460.In some implementations, optical signal generator 404 can transmitaccess control information immediately after an access event, forinstance if the administrator of the system wishes to have real-time, ornear real-time monitoring of access events. In other implementations,optical signal generator 404 can transmit access control informationperiodically, such as every five minutes, or every hour. In yet otherimplementations, optical signal generator 404 transmits access controlinformation automatically when linked to communication network 450 (e.g.a facility Wi-Fi network). If access control server 460 receives, fromoptical signal generator 404 or another device, access controlinformation associated with a user's opening and securing of aparticular electronic locking device 100, access control server 460 cancalculate the duration between the opening event and the securing event.Skilled persons will appreciate that using information obtained fromoptical signal generator 404 is but one method to calculate usageinformation for a particular user or lock and that access control server460 can be configured to use information from other devices in thesystem, such as administration badge 600. In other implementations,access control server 460 can use information generated or recorded bythe server itself to calculate usage information, such as recordsassociated with request messages received from, or transmission ofauthentication information to, optical signal generator 404.

In accordance with at least some embodiments, access control server 460can calculate a monetary fee based, at least in part, on the durationbetween an opening event and a securing event associated with electroniclocking device 100. In some implementations, access control server 460can be configured to immediately charge the user. For instance, the usermay create and register an account associated with access control server460 that entails the user providing credit card information (or otherappropriate information used to execute electronic payment) prior toreceiving authentication information from access control server 460. Inthis manner, access control server 460 can use credit card or otherpayment information to automatically charge a monetary fee associatedwith a user's access to an item or area secured by electronic lockingdevice 100. To illustrate, a user of a parking garage can provide creditcard information to access control server 460 in order to receiveauthentication information for access to the garage. Here, electroniclocking device 100 can be operatively associated with a barrier gate orother blocking member restricting access to the parking facility. Theuser can be charged a fee that is based, at least in part, on theduration between the user's entry into the garage and the user's exitfrom the garage. Or alternatively, on the number of times the userentered the garage during a specified time period. In this example, theuser provides authentication information to actuate the barrier gate forboth ingress and egress. Thereafter, access control informationassociated with the ingress and egress access events can be used todetermine the duration of use. Access control server 460 can beconfigured to contact financial institution 1102 (e.g. via the Internet)to obtain electronic payment in accordance with the user's previouslyprovided payment information. In alternative implementations, accesscontrol server 460 can automatically generate an invoice for the user,for example where electronic payment methods are unsuccessful orunavailable. Skilled persons will appreciate that duration of access isbut one example of usage information that may be utilized to assess afee to users and that other information, for instance the number ofopenings in a predetermined time period, can be utilized depending onthe desired operation of the access control system.

FIG. 12 illustrates an example method 1200 for automatically generatingpayment information based, at least in part, on use of an electroniclocking device. The method 1200 begins at step 1202 where a user,wishing to operate electronic locking device 100, transmits, to accesscontrol server 460, a message requesting authentication information, therequest message originating from a web browser application executing onoptical signal generator 404. In various implementations, access controlserver 460 can be configured to authenticate the user (e.g. viausername, password, ID number, or other credential information) prior toresponding to the request message. In yet other implementations, accesscontrol server 460 can query the user of optical signal generator 404 toobtain additional information, such as the location of the electroniclocking device for which access is requested. It will be appreciated byskilled persons that access control server 460 can utilize other typesof information to verify the user's request, such as biometricinformation measured by optical signal generator 404, time and dateinformation, or GPS information associated with the position of theuser, to provide a few examples.

If the user is indeed authorized to obtain authentication informationfor electronic locking device 100, access control server 460 transmitsauthentication information associated with the specified device to theuser in step 1204. For example, access control server 460 can transmitauthentication information to optical signal generator 404 via BWCinterface 104. In some implementations, access control server 460 mayfacilitate delivery of authentication information to optical signalgenerator 404 by providing the information in a webpage accessible fromthe web browser application executing on optical signal generator 404.In accordance with at least some implementations, optical signalgenerator 404 can be configured to transmit a message to access controlserver 460 to indicate successful receipt of the authenticationinformation.

In step 1206, the user transmits the authentication information toelectronic locking device 100 via wireless optical signal 102 (generatedby optical signal device 404). In various implementations, opticalsignal generator 404 can be configured to generate wireless opticalsignal 102 automatically upon receipt of authentication information fromaccess control server 460. In some implementations, optical signalgenerator 404 can transmit authentication information via VLC methods,such as by causing a light source for a display screen of optical signalgenerator 404 to emit visible light at a certain frequency, pattern, orintensity. To illustrate, upon receipt of authentication informationfrom access control server 460, optical signal generator 404 can beconfigured to automatically display, via an associated display screen, astatic visual feature such as a static image or other fixedtwo-dimensional pattern, or a dynamic visual feature, such as a video(e.g. AVI file, FLV file, MP4 file, etc.) or animation (e.g. GIF file),such that a light source associated with the display screen emits avisible optical signal that conveys at least a portion of theauthentication information. It will be understood that a static visualfeature refers to visual content displayed on the screen that remainssubstantially unchanged for the duration of presentation necessary toconvey the authentication information. Likewise, a dynamic visualfeature refers to visual content that substantially changes at leastonce during the duration of presentation necessary to convey theauthentication information. Skilled persons will appreciate that adynamic visual feature may change in a manner that is not perceptible tothe human eye but may otherwise be detectable by hardware such asphotodetector 130.

In some implementations, access control server 460 can be configured toserve a webpage including the appropriate static visual feature ordynamic visual feature such that viewing the webpage on optical signalgenerator 404 causes presentation, on the display screen, of VLC signalsconveying the authentication information. Optical signal generator 404can be configured to continuously transmit authentication information(e.g. in repeating cycles) until interrupted by the user, for instanceby exiting the web browser application or other software applicationcausing presentation of wireless optical signal 102, or by otherwiseinterrupting generation of the VLC signals. In other implementations,the authentication information can be presented on the display screen(or via another light source) for a predetermined period of time or, forexample where the visual element is a dynamic visual feature, for apredetermined number of cycles. Skilled persons will appreciate that VLCmethods utilizing a light source associated with a display screen ofoptical signal generator 404 is but one method of transmittinginformation and other methods may be used to implement wireless opticalsignal 102. In alternative implementations, wireless optical signal 102may be implemented using other sources of visible light, such as usingone or more LEDs operatively associated with optical signal generator404. For instance, wireless optical signal 102 can be implemented with acamera flash or via another LED or light source of optical signalgenerator 404. Here, the camera flash can comprise an LED that isconfigured to present authentication information by flashing visiblelight pulses in a pattern or at a certain frequency or intensity. Insome implementations, the camera flash or other LED can modulate thecolor of the visible light emitted in a particular pattern. In yet otherimplementations, wireless optical signal 102 can be implemented usingnon-visible optical signals, for instance via components of opticalsignal generator 404 configured to produce IRC signals or UVC signals.

In step 1208, optical signal generator 404 writes access eventinformation to memory sites associated with the optical signalgenerator. For instance, upon transmission of authenticationinformation, optical signal generator 404 can record informationassociated with the transmission of authentication information, such asthe date and time that transmission was initiated. In someimplementations, optical signal generator 404 can record additionalinformation associated with the transmission, such as the GPS locationof optical signal generator 404 at the time of transmission. If validauthentication information is transmitted to electronic locking device100 in step 1208, the user can operate (e.g. open) electronic lockingdevice 100 in step 1210. Here, electronic locking device 100 can also beconfigured to write access event information to memory sites associatedwith the locking device, such as the time and date that authenticationinformation was received via wireless optical signal 102. In step 1212,the user again transmits authentication information to electroniclocking device 100 to operate (e.g. lock or otherwise secure) thedevice. In some implementations, the user can transmit the sameauthentication information transmitted in step 1206. Here, the user caninitiate transmission using optical signal generator 404, for example byusing the same display pattern utilized in step 1206, or by againrequesting authentication information from access control server 460. Inother implementations, the information used to lock or secure the devicecan be a generic locking code, wherein the same authenticationinformation is used to secure multiple locking devices deployed in thesystem. In step 1214, optical signal generator 404 writes access eventinformation associated with the second transmission of authenticationinformation (e.g. to lock or secure the device) to memory sitesassociated with the optical signal generator. The information recordedby optical signal generator 404 in this step 1214 may be the same typeor category of information recorded in step 1208 (e.g. date and time oftransmission). Electronic locking device 100 can also be configured towrite event information to memory sites associated with the lockingdevice, such as the time and date the locking device was secured by theuser.

Next, access event information is transmitted to access control server460 in step 1216. To illustrate, in accordance with at least someembodiments, optical signal generator 404 can be configured toautomatically transmit access event information to access control server460 immediately after writing such information to memory sites (i.e.immediately following completion of step 1214). Optical signal generator404 may be configured to transmit access event information via BWCinterface 104. In some implementations, BWC interface 104 is establishedbetween optical signal generator 404 and access control server 460 usinga cellular data network protocol or other standard wirelesscommunication protocol. In other implementations, optical signalgenerator 404 can attempt transmission of access event information atpredetermined intervals, such as every hour after an access event. Inyet other implementations, access event information can be retrievedfrom electronic locking device 100 and thereafter transmitted to accesscontrol server 460. For instance, administration badge 600 can retrieveaccess event information from electronic locking device 100. Thereafter,administrative badge 600 can be configured to automatically transmitaccess event information to access control server 460 (e.g. via BWCinterface 104). Alternatively, administration badge 600 can beconfigured to transmit access event information to system monitor 700where it is then transmitted to access control server 460.

In step 1218, access control server 460 calculates a monetary valueassociated with use of electronic locking device 100, the monetary valuebeing calculated based, at least in part, on the access eventinformation received in step 1216. In some implementations, accesscontrol server 460 can be configured to use access event informationgenerated by the server to calculate the monetary value, for instanceinformation written to memory sites contemporaneously with transmissionof authentication information from the server to optical signalgenerator 404. To illustrate, access event information may indicate thata user of the system accessed a particular electronic locking device at1:00 pm and thereafter secured the locking device at 5:00 pm on the sameday. In this particular example, the value assigned for access to thearea or item secured by the locking device is $10.00 per hour. Based, atleast in part, on the access event information indicating the time theuser accessed (and later secured) electronic locking device 100, accesscontrol server 460 may calculate a monetary value of $40.00 for the fourhours of access to the area or item secured by the locking device. Inanother example, access event information may indicate that a useraccessed a particular locking device three times during a 24-hourperiod. Here, the value of using the locking device is $10.00 per use(or opening). In this example, access control server 460 can calculate amonetary value of $30.00 associated with use of the locking device (i.e.$10.00 for each of the 3 openings). Skilled persons will appreciate thataccess control server 460 can be configured to calculate monetary valuebased on other information, for example the number of openings permonth, the duration between openings, or a combination of metrics (e.g.duration of use and an additional flat fee per use).

Lastly, in step 1220, access control server 460 automatically chargesthe user based, at least in part, on the monetary value calculated instep 1218. For example, if access control server 460 calculated amonetary value of $30.00 in step 1218, it can be configured toautomatically charge the user $30.00. Alternatively, it may charge anadditional fee, such as a use fee. For instance, if the monetary valuecalculated in step 1218 was $30.00, access control server 460 can assessan additional service fee (or similar charge) of $2.50 for a totalcharge to the user of $32.50. Depending on the desired operation of thesystem, access control server 460 can use known electronic methods tocharge the user. In this example, a user wishing to access electroniclocking device 100 may first register an account and provide credit cardinformation (or other electronic payment information) to be stored bythe system, such as in memory sites of access control server 460. Accesscontrol server 460 can be configured to use stored electronic paymentinformation to automatically obtain payment, for example by initiating acharge to the user's credit card or bank account (according to knownmethods). In other implementations, for example where electronic paymenttechnologies are unavailable or unsuccessful, access control server 460can be configured to generate an invoice or other document designed torequest or collect payment from the user. In yet other examples, accesscontrol server 460 can apply a charge to an account associated with theuser (e.g. if it is desired to extend credit terms to the user). It willbe understood that access control server 460 may employ any knownmethods and technologies for charging users based on the monetary valuecalculated in step 1218.

While this method is illustrated by way of access control server 460calculating a value associated with use of electronic locking device(see step 1218 above), and thereafter automatically charging a user ofelectronic locking device based, at least in part, on the valuecalculated (see step 1220 above), it will be appreciated that inalternative implementations, such steps may be performed by anotherdevice (or combination of devices) deployed in the access controlsystem. For example, optical signal generator 404 may, prior totransmission of access event information (see step 1216 above),calculate a monetary value based, at least in part, on the access eventinformation. Optical signal generator 404 can be configured to transmit,to access control server 460, the access event information and thecalculated monetary value. In this example, access control server 460uses the monetary value calculated by optical signal generator 404 tocharge users. In some implementations, such steps may be performed byadministrative badge 600. For instance, if it is desired to use accessevent information from memory sites of electronic locking device 100, asystem administrator can retrieve access event information from thelocking device using administrative badge 600 (as described above).Administrative badge 600 can be configured to use the retrieved accessevent information to calculate a monetary value associated with use ofelectronic locking device 100. If administrative badge 600 is configuredsuch that it can communicate with devices across the Internet (e.g. viaa cellular data network), administrative badge 600 can be configured tocommunicate with a user's financial institute to charge the user'scredit card. For instance, administrative badge 600 can communicate withaccess control server 460, such as by way of communication network 450,to retrieve electronic payment information for a particular user.Administrative badge 600 can then use the retrieved electronic paymentinformation to charge the user's credit card or bank account. Skilledpersons will appreciate that these examples are illustrative of variousimplementations of the method and are not intended to limit the scope ofthe method steps to any particular device or system arrangement.

In accordance with various embodiments, a system administrator or otheruser of the system can provide authentication information for anelectronic locking device to another user of the system. For instance, auser may have authority to control who accesses a particular electroniclocking device, such as where the user has installed the locking deviceon the user's home or office door. The user possessing authority tocontrol access to the electronic locking device can modify accesscontrol permissions for the device by communicating with access controlserver 460. In various implementations of this disclosure, the user cancommunicate with access control server 460 using a web browserapplication or another mobile app software application executing on anyelectronic device capable of communicating with access control server460 via the methods and protocols described herein. For instance, a usercan utilize a web browser application executing on optical signalgenerator 404. Here, optical signal generator 404 can be implemented asa smart device, such as a commercially available tablet or smartphonethat is capable of exchanging access control information with accesscontrol server 460, such as via BWC interface 104 and communicationnetwork 450.

Turning now to FIG. 13, access control information can be displayed viaa webpage accessible from a web browser application. In the exampleillustrated by FIG. 13, a user can provide access credentials to accesscontrol server 460 in order to view and modify access controlinformation. In this example, the user is prompted to provide a usernameand password prior to accessing the information. Upon providing validaccess credentials, access control server 460 can be configured toprovide the user with access control information associated with alllocking devices that the user may open. It will be appreciated thatother methods of authenticating the user can be employed depending onthe desired operation of the access control system. For instance, insome implementations, communication network 450 can comprise an internalintranet, nullifying many of the security concerns associated withtransmitting information via a publically accessible Internet. Thesystem may even be configured such that it does not require an accesscredential to be submitted by the user. Skilled persons will understandthat desired security safeguards of a particular access control systemmay dictate variations in the authentication process used to grantaccess to view and modify access control information.

FIG. 14 illustrates one example of a user interface for displayingaccess control information to the user, via a webpage accessible from aweb browser application. To provide additional context to the user,electronic locking device 100 can be associated with identifyinginformation. For instance, in FIG. 14 a particular electronic lockingdevice 100 is labeled “Front Door,” allowing the user to quicklyidentify where that particular locking device is installed within theaccess control system, or which item or area it is intended to secure.In accordance with various implementations, locking devices that theuser has permission to open are further differentiated by the degree ofcontrol that the user may exert over the locking device. For example,the locking devices labeled “Front Door” and “My Office” in FIG. 14 areinstalled on entry points owned or administered by the user. However,the locking device labeled “Beth—Front Door” is installed on an entrypoint owned or administered by another individual in the access controlsystem. In various implementations, access control server 460 can beconfigured to permit the user to modify access control permissions forlocking devices owned or administered by the user. For locking devicesin the access control system that are owned or administered by otherindividuals, access control server 460 can be configured such that theuser has permission to view, but not modify, the access permissions. Asillustrated in FIG. 14, the locking devices owned or administered by theuser can be, for convenience, listed separately from locking devicesowned or administered by other individuals in the system. In thisexample, the locking devices owned or administered by the user arelabeled “My Locks,” whereas the locking devices owned or administered byother users are labeled “Locks you are allowed into.”

As further illustrated by FIG. 14, the user can access any of the listedlocks by selecting, in the webpage, the button labeled “Open,” forexample by pressing the appropriate location on a touch-sensitivedisplay screen associated with optical signal generator 404. If the userwishes to open a locking device, access control server 460 can beconfigured to cause delivery of authentication information to opticalsignal generator 404 by way of the webpage. To illustrate, if the userwishes to open the locking device labeled “Front Door,” the user canselect the appropriate “Open” button. Access control device 460 can beconfigured to respond to selection of the “Open” button by generating,within the webpage or by redirecting to a new webpage, a display patternconfigured to generate a VLC optical signal conveying authenticationinformation for the selected locking device. For instance, FIG. 15illustrates an example user access interface 1500 depictingpresentation, within a webpage, of an example dynamic visual code 1510that causes wireless optical signal 102 (generated in this example by alight source associated with the display screen) to conveyauthentication information. Here, access control server 460 isconfigured to provide, for display on a web browser, a webpage includingan animation or video. In this illustration, dynamic visual code 1510 isa dynamic visual feature that includes a plurality of substantiallydifferent colored regions that are displayed in succession duringpresentation of the animation or video. Although FIG. 15 depicts dynamicvisual code 1510 as a video or animation comprising a series of black,white, and off-colored regions, it will be understood by skilled personsthat dynamic visual code 1510 can be implemented using other dynamic orstatic visual content, such as different colored regions or shapes, aphotograph, or even a clip of a published film or video, such as a videouploaded to the YouTube video community. In this implementation, accesscontrol server 460 can cause optical signal generator 404 to present theauthentication information as wireless optical signal 102 by displayingon a screen of the optical signal generator, the visual content of thewebpage or by otherwise providing information to optical signalgenerator to cause display of the visual content on the display screen.

To illustrate further, access control server 460 can serve a webpagethat includes a dynamic visual feature that alternates betweendisplaying the different colored rectangles depicted in FIG. 15. In thisexample, the intensity of light in the visual light wavelength spectrum(generated by a light source associated with the display screen) isgreater during display of the white rectangle than during display of theoff-colored rectangle or the black rectangle. Access control server 460,by causing the alternating display of these rectangles of varying hue,such as by an animation or video, causes the display screen to emit VLCsignals in the form of optical pulses (e.g. pulses of varyingintensity). Photodetector 130 can, for example, measure the intensity(e.g. lux) of the pulses and convert (e.g. sampling the optical signalsto perform analog-to-digital conversion) the optical signal into acorresponding electrical signal. In this manner, VLC signals generatedby a light source associated with the display screen can, according tothe pattern of the visual content of the webpage, transmit informationserially (i.e. one bit at a time) to photodetector 130.

To illustrate one example, ternary (or binary if desired) information,such as an access code comprising a ternary number sequence, can betransmitted by modulating a light source associated with the displayscreen. In accordance with various implementations, dynamic visual code1510 can be configured to modulate the light source associated with thescreen in a manner generating three distinct states in the resultingoptical signal. Here, the highest intensity (i.e. the white rectangle)can correspond to logic level 2, the off-colored rectangle cancorrespond to logic level 1, and the lowest intensity (i.e. the darker,black rectangle) can correspond to logic level 0. The pattern, duration,or frequency according to which the white, off-color, and blackrectangles are alternately displayed will depend, at least in part, onthe ternary information to be transmitted. Photodetector 130 can beconfigured to convert the optical pulses of varying intensities ofvisual light back into ternary information, for example according tochanges in measured illuminance. Photodetector 130 can then provide theternary information to microprocessor 112, for example to initiate anaccess event such as the unlocking of an entry point. Ternaryinformation is but one example of information that can be transmittedvia wireless optical signal 102 and skilled person will appreciate thatinformation formatted according to other rules and systems may haveutility. It will be further appreciated that alternately displayingregions of different hues on a webpage is but one example of utilizingVLC methods to transmit information via wireless optical signal 102 andthat other methods and techniques may have utility depending on thesystem. For instance, access control server 460 can be configured toserve a webpage including other types of images, such as displayingpatterns of images comprising different colored shapes or logos. In yetother implementations, access control server 460 can be configured suchthat selecting the “Open” button within the webpage causes delivery of amessage to optical signal generator 404. For example, access controlserver 460 may transmit a message including authentication informationalong with instructions to generate optical signals including theauthentication information via an LED or other optical device associatedwith optical signal generator 404, such as a device capable ofgenerating an IRC or UVC signal.

Referring again to FIG. 14, in accordance with at least some embodimentsa user can modify access permissions for certain locking devices thatthe user owns or administers by selecting, in the webpage, the buttonlabeled “Allowed.” For instance, if the user wishes to modify accesspermissions for the locking device labeled “Front Door,” the user canselect the appropriate “Allowed” button (i.e. the “Allowed” buttonproximate to the “Front Door” label) to view information associated withthat particular locking device. As described in this disclosure, accesscontrol server 460 can be configured to display information associatedwith “Front Door” via a webpage accessible from a web browserapplication, such as a browser application executing on optical signalgenerator 404. Turning to FIG. 16, an access control server 460 canprovide a webpage including information associated with the lockingdevice labeled “Front Door,” such as a list of individuals thatpresently have permission to open that particular locking device. Insome implementations, access control server 460 can also provide, viathe webpage, a list of other individuals known or registered in thesystem. To illustrate, FIG. 16 depicts a list of individuals registeredin the system. However, the individuals that presently haveauthorization to open the “Front Door” locking device are visiblydistinguished from individuals who do not presently have suchauthorization. Here, individuals with authorization to open “Front Door”are distinguished visually with a symbol; in this case, the symbolresembles a generic mechanical key. It will be appreciated that otherappropriate means for distinguishing between individuals may beutilized, for instance logos, colors, or labels. In variousimplementations, access control server 460 can be configured to presentadditional information in the webpage, such as the number of times thatan individual is permitted to access a device, or the duration orscheduled times that an individual's access permissions are valid.

In accordance with at least some embodiments, a user can modify accesspermissions for a particular locking device, for example to provideanother individual with access to the device. Referring still to FIG.16, a user may wish to modify access permissions for “Front Door” toprovide access permissions for the individual labeled “Becca.” Here, theuser can initiate modification of access permissions associated with“Front Door” by selecting the individual labeled “Becca.” Skilledpersons will appreciate that displaying a list of individuals associatedwith a particular locking device is but one example of variousappropriate methods of presenting and modifying access controlinformation associated with the system. In this example, access controlserver 460 can be configured to display, in response to a user'sselection of the individual labeled “Becca,” access permissioninformation that may be associated with Becca. For example, turning nowto FIG. 17, access control server 460 can be configured to permit theuser to specify how access permissions are modified, for example viatext fields or selection menus. As illustrated in FIG. 17, accesscontrol server 460 can be configured to respond to the user's selectionof Becca by providing (i.e. serving) a webpage that displays options forissuing access permissions to Becca. The user may be provided with anoption to issue access permissions to a specific locking device owned oradministered by the user. In this example, the user can select betweenvarious locking devices labeled “Front Door,” “Office,” “Locker 1,” and“Locker 2.” It will be appreciated that FIG. 17 depicts only one exampleof access control information associated with a user and that otherinformation may have utility depending on the desired operation of thesystem.

Access control server 460 can be configured to permit the user to issueor modify access permissions to a particular locking device. Forinstance, the user can select the “Front Door” device to provide Beccawith authorization to open the locking device labeled “Front Door.” Uponselecting the Front Door device, access control server 460 can beconfigured to allow the user to further modify or specify the accesspermissions. For example, as illustrated in FIG. 18, the user canselect, via the drop down menu, a period of time during which Becca'spermissions are valid. Skilled persons will appreciate that the accesscontrol information depicted in FIG. 18 is illustrative in nature andthat other information may be displayed and modified by the user. Insome implementations the user can provide access to a device on certaindays of the week, or in response to the occurrence of an event, such asthe receipt of payment from a user. By selecting the “Give” button (asdepicted in FIG. 18), the user can provide access permissions to Beccabased on the user's input, thereby modifying the access permissionsassociated with the Front Door locking device and with Becca. Uponproviding access permissions to Becca, access control server 460 can nowindicate (via any appropriate visual method) that Becca has permissionto open the Front Door device for one hour, as illustrated in FIG. 19.

It will be understood that, depending on the desired operation of thesystem, access control server 460 may perform various tasks to updateaccess permissions for a locking device. In the current example, a userof the system requests authentication information from access controlserver 460, for example via a webpage, prior to operating a lockingdevice. In this implementation, access control server 460 can simplyupdate access control information stored on memory sites of accesscontrol server 460 or memory sites associated with the server. Toillustrate further, access control server 460 can maintain, in memorysites thereof, a list of individuals that are permitted to open aparticular electronic locking device. If an individual is grantedpermission to open the locking device, access control server 460 may addthe name of the individual (or other identifying information) to thelist. Thereafter, when the user requests authentication information forthe locking device, access control server 460 can be configured toverify that the individual has permission (e.g. by checking the list ofindividuals in memory sites) prior to delivering authenticationinformation. This is but one example illustrating modification of accesspermissions and is not intended to limit the scope of this disclosure toany particular method.

During the period of time that Becca's access permissions are valid,Becca can access a webpage (e.g. from a web browser application) to openthe Front Door locking device. For instance, Becca can login to a securewebsite to communicate with access control server 460 (as describedabove with reference to FIG. 13) and select an “Open” button associatedwith the Front Door device (as described above with reference to FIG. 14and FIG. 15). In various implementations, Becca can receive anelectronic message comprising instructions for opening the Front Doordevice. To illustrate, Becca can receive an email message via opticalcommunication device 404 containing a link or other instructions thatcause optical signal generator 404 to transmit authenticationinformation for the Front Door device. To provide yet another example,Becca can receive, at optical signal generator 404, a short messageservice (SMS) text message containing a reference to a webpage. Areference to a webpage can be any information permitting a computingdevice (e.g. smart device) to navigate to the webpage, including auniform resource locator (URL) hyperlink or other information associatedwith a resource hosted on the Internet. Turning now to FIG. 20, anaccess notification message 2000 can include additional information toprovide context for the reference to the website. Here, accessnotification message 2000 is an SMS text message and the reference tothe website is a URL hyperlink. In the example depicted by FIG. 20, anSMS text message accessed via optical signal generator 404 includescontextual information that suggests the transmitted URL hyperlinkprovides access to “John Smith's Front Door.” While a URL hyperlink isincluded in the message depicted in FIG. 20, it will be understood thatsuch a message may contain information in other formats. As an example,the message delivered to Becca can be a multimedia message service (MMS)message comprising an animation or video that, when viewed, presentsauthentication information as VLC signals generated by a display screenassociated with optical signal generator 404.

The URL hyperlink depicted in FIG. 20 can be selected (or input by theuser directly into a web browser) to thereby cause a web browserapplication executing on optical signal generator 404 to navigate to aparticular web address. Turning to FIG. 21 to illustrate, if the URLhyperlink depicted in FIG. 20 is selected or otherwise input into a webbrowser application, the browser can display a webpage that includesvisual content such as an image or animation that, when displayed on adevice, causes a light source associated with a display screen togenerate a VLC optical signal conveying at least a portion of theauthentication information associated with the electronic locking deviceidentified as “John Smith's Front Door.” Here, access control server 460may provide the webpage automatically if requested by optical signalgenerator 404. In some implementations, access control server 460 canuse an HTTP cookie or other information to identify optical signalgenerator 404 as the authorized device associated with the URLhyperlink. This HTTP cookie can be placed on optical signal generator404, for instance in memory associated with the web browser application.Thereafter, any device attempting to access the resource associated withthe URL hyperlink (e.g. where the SMS message is forwarded from opticalsignal generator 404) must provide the HTTP cookie to access controlserver 460 in order to access the resource. In various implementations,devices that do not provide the HTTP cookie are denied access whereinaccess control server 460 does not provide the webpage. In this manner,authentication information may only be usable by the user of opticalsignal generator 404.

In other implementations, access control server 460 may only provide thewebpage or other resource associated with the URL hyperlink if therequest is received during the time period that access permissionsassociated with a user of optical signal generator 404 are valid. Forexample, access control server 460 may identify the user or the deviceby way of the URL hyperlink information, device information, or userinput. To illustrate, in some embodiments access control server 460 isconfigured to first provide a challenge-response interface requiring theuser of optical signal generator 404 to input a response. For example,upon navigating to the URL hyperlink, the user of optical signalgenerator 404 may provide a username and password, or other credential.Upon authenticating the user, access control server 460 canautomatically provide the webpage or, in some implementations, mayadditionally reference time information to determine if the request isreceived during a valid access window. For instance, if accesspermissions associated with the user authorize access to electroniclocking device 100 only between the hours of 8:00 am and 5:00 pm, accesscontrol server 460 may determine whether the request is received duringthat time window before providing the webpage. In some implementations,optical signal generator 404 may provide access control server 460 withinformation identifying the signal generator or the user, such as amedia access control (MAC) address or biometric information associatedwith the user. In accordance with certain implementations, accesscontrol server 460 can determine whether to provide the requestedwebpage in response to at least one of the device information, userinformation, user input, or time information associated with therequest.

The webpage can utilize any suitable method to cause generation of theauthentication information. To illustrate, FIG. 21 depicts an exampleuser access interface 2100 depicting presentation, within a webpage, ofan example static visual code 2110 that causes wireless optical signal102 (generated in this example by a light source associated with thedisplay screen) to convey the authentication information associated withthe electronic locking device identified as “John Smith's Front Door.”It will be appreciated that static visual code 2110 can be any staticvisual pattern, such as a photograph, a two-dimensional barcode such asa Data Matrix barcode, QR code, or high capacity color barcode (HCCB),to identify just a few examples of static two-dimensional visualcontent. The two-dimensional pattern depicted in FIG. 21 as staticvisual code 2110 is but one example of two-dimensional visual contentthat can be used to present authentication information on the displayscreen and is not intended to limit the presentation to any particularpattern or color palette. In alternate embodiments, for instance asdescribed elsewhere in this disclosure, the webpage can include ananimation or video (or other dynamic image) causing a light source ofthe display screen to present wireless optical signal 102 as a pluralityof regions of varying hues that are alternately displayed to convey theauthentication information. It will be appreciated that other methodsand techniques of transmitting information via optical signals may beutilized, for instance the webpage can display a movie clip designed topresent authentication information as visible light signals generated bythe display screen.

While the example provided in this disclosure illustrates modificationof access permissions for a particular electronic lock by way oftransmitting and/or receiving access control information via signalsgenerated by visual content of a webpage, it will be understood thataccess control server 460 can be configured to display and modify otherinformation as desired. For instance, electronic locking devices can beadded to or registered with an access control system by transmittinginformation associated with the locking device to access control server460 via a webpage. Turning to FIG. 22 now, access control server 460 canbe configured to determine whether a particular user or administrator ofthe system is associated with any locking devices, for example by way ofhaving access permissions to a locking device. If access control server460 determines that the user is not associated with any registeredlocking devices, access control server 460 can be configured to providea webpage that displays this information to the user and prompts theuser to register new locking devices or identify previously registeredlocking devices.

To illustrate, as depicted in FIG. 22, a user that is not presentlyassociated with any locking devices or, alternatively, a user who wishesto add additional locking devices can select the button labeled “Addlocks” to provide locking device information to the system. Inaccordance with various embodiments, access control server 460 canprompt the user to input a serial number or other identifyinginformation associated with the locking device. In otherimplementations, the user can upload information associated with thelocking device that is stored in memory sites of electronic devices incommunication with access control server 460, for example optical signalgenerator 404 or administration badge 600. Referring now to FIG. 23, ifa user selects the “Add locks” button, access control server 460 canprompt the user, via the webpage interface, for information associatedwith the locking device, such as a name (e.g. Front Door) and serialnumber. Skilled persons will appreciate that other information may haveutility in the system and that a name and serial number are but oneexample of information that can be associated with a locking device.

While various implementations are described herein as utilizing awebpage interface to display and exchange information with users of anaccess control system, persons of skill will appreciate that a webpageis but one example of displaying access control information to the userand other appropriate methods may have utility depending on thecharacteristics of the system and devices deployed therein. Forinstance, access control information can be viewed and/or exchanged byutilizing a dedicated software application or other computer programexecuting on optical signal generator 404, as described above withrespect to FIG. 10.

EXAMPLE EMBODIMENTS

The following examples pertain to further embodiments.

Example 1 is an electronic locking device responsive to a light-emittingdiode (LED) of a smart device so as to unlock an entry point in responseto receiving authentication information conveyed from the LED to theelectronic locking device, the electronic locking device comprising:wireless communication circuitry to exchange access control information,the access control information including stored authentication and audittrail information for respectively, updating and reviewing user accessof the electronic locking device; a memory for storing the accesscontrol information made available to the electronic locking devicethrough the wireless communication circuitry; a photodetector arrangedto confront a user holding the smart device so as to receive an opticalsignal emitted by the LED and produce from it an electrical signalcorresponding to the optical signal, the optical and electrical signalseach representing the received authentication information; andelectrical circuitry that, in response to the electrical signal,determines from it the received authentication information and comparesit to the access control information stored in the memory operativelyassociated with the electrical circuitry so as to unlock the entry pointin response to the received authentication information corresponding tothe stored authentication information thereby permitting access to theuser holding the smart device.

Example 2 includes the electronic locking device of example 1, in whichthe photodetector is an imager.

Example 3 includes the electronic locking device of example 2, in whichthe imager is a complementary metal-oxide-semiconductor (CMOS) imagesensor or a charge-coupled device (CCD) image sensor.

Example 4 includes the electronic locking device of example 1, in whichthe entry point is a door or a turnstile.

Example 5 includes the electronic locking device of example 1, in whichthe optical signal comprises a pattern of flashes emitted by atouchscreen or a camera flash including the LED.

Example 6 includes the electronic locking device of example 1, in whichthe pattern of flashes includes a start sequence of flashes, and theelectrical circuitry, in response to detecting the start sequence, isconfigured to change its operative state from a low power consumptionstate to an event initiation state, the low power consumption statecharacterized by the electrical circuitry forgoing attempts to comparethe received authentication information from the electrical signal andthe event initiation state characterized by the electrical circuitryattempting to process the received authentication information.

Example 7 includes the electronic locking device of example 1, in whichthe wireless communication circuitry comprises a wireless networkingradio, the wireless networking radio configured to provide wirelesspersonal area network (WPAN) or wireless local area network (WLAN)communications for exchanging the access control information.

Example 8 includes the electronic locking device of example 7, in whichthe smart device comprises a first smart device, and in which the WPANcommunications are received from a second smart device, different fromthe first smart device, for monitoring the audit trail information.

Example 9 includes the electronic locking device of example 7, in whichthe WLAN communications are received from a remote administrationsystem.

Example 10 includes the electronic locking device of example 1, in whichthe optical signal comprises a visual depiction of two-dimensionaloptical code.

Example 11 includes the electronic locking device of example 10, inwhich the two-dimensional optical code comprises a Data Matrix code.

Example 12 includes the electronic locking device of any one of examples1-11, in which the wireless communication circuitry comprises aninfrared receiver.

Example 13 includes the electronic locking device of any one of examples1-11, further comprising: a housing encompassing the photodetector andincluding sidewalls; and a window recessed from the sidewalls andcovering the photodetector so that a display screen of a smart device,when confronting the window and pressed against the sidewalls,suppresses ambient light from reaching the photodetector.

Example 14 is a method, performed by a smart device having alight-emitting diode (LED) and a wireless networking radio, of causingan electronic locking device to unlock an entry point in response toauthentication information conveyed from the LED to the electroniclocking device, the method comprising: transmitting, from the wirelessnetworking radio to a server, a request to configure the server toprovide the authentication information to the smart device acting as aclient accessing the server through at least one of a wireless wide areanetwork (WWAN) or a wireless local area network (WLAN); receiving, inresponse to the request, information that configures the LED to presentthe authentication information as an optical signal emitted by the LED;and presenting from the LED to a photodetector of the electronic lockingdevice the optical signal that causes the electronic locking device tounlock the entry point.

Example 15 includes the method of example 14, in which the smart deviceincludes a camera flash comprising the LED.

Example 16 includes the method of example 14, in which the smart deviceincludes a user interface display comprising the LED.

Example 17 includes the method of example 16, in which the userinterface display is an organic LED (OLED) display comprising the LED.

Example 18 includes the method of example 16, in which the presentingcomprises rendering a webpage including a dynamic visual feature thatchanges visual content appearing on the user interface display so as toconvey the authentication information as the optical signal emitted bythe user interface display.

Example 19 includes the method of any one of examples 14-18, furthercomprising: receiving a short message service (SMS) or multimediamessaging service (MMS) message including a reference to a webpage thatis available from the server, the webpage including the information thatconfigures the LED to present the authentication information; andgenerating the request for the webpage.

Example 20 includes the method of any one of examples 14-18, furthercomprising generating the request according to a hypertext transferprotocol (HTTP), a hypertext transfer protocol secure (HTTPS), a filetransfer protocol (FTP), or a secure file transfer protocol (SFTP).

Example 21 includes the method of example 14, in which the receivingcomprises receiving the information through a mobile app softwareapplication on the smart device, the information including instructionsconfiguring the mobile app software application to control light emittedby the LED based on the instructions.

Example 22 includes the method of example 21, in which the mobile appsoftware application is a native mobile application, a mobile webapplication, or a hybrid mobile application.

Example 23 is a computer-readable storage medium having instructionsstored thereon that, when performed by a server of authenticationinformation for unlocking an entry point controlled by an electroniclocking device, cause the server to: receive through a computer networka request from a smart device acting as a client accessing the serverthrough at least one of a wireless wide area network (WWAN) or awireless local area network (WLAN), the request associated with thesmart device seeking the authentication information by which to unlockthe entry point; and provide, in response to the request, information toconfigure a light-emitting diode (LED) of the smart device so that itemits the authentication information in the form of an optical signaldetectable by a photodetector of the electronic locking device.

Example 24 includes the computer-readable storage medium of example 23,further comprising instructions to transmit a set of machine-readableinstructions that, when performed by the client, configure a displayscreen including the LED to change its visual appearance and therebyemit the optical signal.

Example 25 includes the computer-readable storage medium of example 23,in which the client is a mobile app software application.

Example 26 includes the computer-readable storage medium of example 24,in which the mobile app software application is a web browser.

Example 27 includes the computer-readable storage medium of example 23,in which the server is a website server and the information to configurethe LED comprises a dynamic image format provided on a webpage of thewebsite server.

Example 28 includes the computer-readable storage medium of example 23,in which the server is a website server and the information to configurethe LED comprises a video provided on a webpage of the website server.

Example 29 includes the computer-readable storage medium of example 23,in which the server is a website server and the information comprises astatic image provided on a webpage of the website server.

Example 30 includes the computer-readable storage medium of any one ofexamples 23-29, in which the instructions further configure the serverto determine whether access to the entry point is permitted in responseto the request.

Example 31 is a method, performed by the electronic locking device ofany one of examples 1-13, the method comprising: converting the opticalsignal to the electrical signal; determining the received authenticationinformation; and actuating a locking component to unlock the entrypoint.

Example 32 is a smartphone having a machine-readable storage deviceincluding machine-readable instructions that configure the smartphone toperform the method of any one of examples 14-22.

Example 33 is a method, performed by a user, of using a smart device toperform the method of any one of examples 14-22.

Example 34 includes the method of example 33, further comprising tappinga link in a text message to access a webpage that provides a flashpattern, in which the webpage is accessible for a predeterminedduration.

Any reference in this disclosure to “one embodiment,” “an embodiment,”“some embodiments,” “various embodiments,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is included in at least one embodiment of this disclosure.The appearances of such phrases, and variations thereof, includingreferences to “implementations,” are not necessarily all referring tothe same embodiment or implementation. When a particular feature,structure, or element is described in connection with any embodiment orimplementation, it is understood that it is within the purview ofpersons of skill to affect such feature, structure, or element inconnection with any of the other embodiments and implementations.

It should be understood that as used in this disclosure and throughoutthe claims that follow, the phrase “A or B” means any one of (A), (B),or (A and B), which is synonymous with the phrase “A and/or B.”Alternatively, just a “/” may be use for conciseness. For example, thephrase “A/B” also means “A or B.” The phrase “at least one of A, B, andC” means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, andC). Further, as used in this disclosure and throughout the claims thatfollow, the meaning of “in” includes “in” and “on” unless the contextclearly prescribes otherwise. The terms “comprising,” “having,” and“including” are synonymous, unless the context dictates otherwise. Asused in this disclosure, the terms “conveying” and “carrying” aredescribed with reference to information included in a communicationsignal and are synonymous, unless the context dictates otherwise.

Although embodiments have been described with reference to a number ofillustrative embodiments and implementations thereof, it will beappreciated that numerous other modifications and embodiments can bedevised by skilled persons without departing from the spirit and scopeof the underlying principles of this disclosure. The scope of thisdisclosure should, therefore, be determined only by the followingclaims.

It is claimed:
 1. An electronic locking device for multi-channelwireless communications and responsive to a light-emitting diode (LED)of a smart device so as to unlock an entry point in response toreceiving, through a first communication channel, authenticationinformation conveyed from the LED to the electronic locking device, theelectronic locking device comprising: wireless communication circuitryconfigured to provide a second communication channel, different from thefirst communication channel, to exchange access control information, theaccess control information including stored authentication and audittrail information for respectively, updating and reviewing user accessof the electronic locking device; a memory for storing the accesscontrol information made available to the electronic locking devicethrough the wireless communication circuitry; a photodetector arrangedto confront a user holding the smart device so as to receive, throughthe first communication channel, an optical signal emitted by the LED asa sequence of user-perceptible flashes of light, the flashes of lighteach having a wavelength substantially in the visible light spectrum,and thereby produce, from the flashes of light, an electrical signalcorresponding to the optical signal, the optical and electrical signalseach representing the received authentication information; andelectrical circuitry that, in response to the electrical signal,determines from it the received authentication information and comparesit to the access control information stored in the memory operativelyassociated with the electrical circuitry so as to unlock the entry pointin response to the received authentication information corresponding tothe stored authentication information thereby permitting access to theuser holding the smart device.
 2. The electronic locking device of claim1, wherein the sequence of user-perceptible flashes of light is emittedby a touchscreen or a camera flash including the LED.
 3. The electroniclocking device of claim 2, wherein the touchscreen or the camera flashincluding the LED is a multicolor light source configured to emittemporally separated flashes of light in a plurality of wavelengthbands, and wherein the sequence of user-perceptible flashes of lightcomprises a first flash of light having a first wavelength in thevisible light spectrum and a second flash of light having a secondwavelength in the visible light spectrum, the second wavelength beingdifferent than the first wavelength, whereby the difference between thefirst wavelength and the second wavelength results in a correspondingdifference in output of the photodetector.
 4. The electronic lockingdevice of claim 2, wherein the sequence of user-perceptible flashes oflight includes a start sequence of flashes, and the electricalcircuitry, in response to detecting the start sequence, is configured tochange its operative state from a low power consumption state to anevent initiation state, the low power consumption state characterized bythe electrical circuitry forgoing attempts to compare the receivedauthentication information from the electrical signal and the eventinitiation state characterized by the electrical circuitry attempting toprocess the received authentication information.
 5. The electroniclocking device of claim 1, wherein the wireless communication circuitrycomprises a wireless networking radio, the wireless networking radioconfigured to provide wireless personal area network (WPAN) or wirelesslocal area network (WLAN) communications for exchanging the accesscontrol information.
 6. The electronic locking device of claim 5,wherein the WLAN communications are received from a remoteadministration system.
 7. The electronic locking device of claim 5,wherein the WPAN communications are implemented according to astandardized wireless networking communication protocol selected fromthe group consisting of a Bluetooth protocol, an Infrared DataAssociation (IrDA) protocol, an IEEE 802.15.4 (ZigBee) protocol, aZ-Wave protocol, and an IEEE 1902.1 (RuBee) protocol.
 8. The electroniclocking device of claim 5, wherein the smart device comprises a firstsmart device, and in which the WPAN communications are received from asecond smart device, different from the first smart device, formonitoring the audit trail information.
 9. The electronic locking deviceof claim 8, wherein the first smart device is a smartphone.
 10. Theelectronic locking device of claim 1, further comprising: a housingencompassing the photodetector and including sidewalls; and a windowrecessed from the sidewalls and covering the photodetector so that adisplay screen of a smart device, when confronting the window andpressed against the sidewalls, suppresses ambient light from reachingthe photodetector and interfering with the optical signal.
 11. Theelectronic locking device of claim 1, wherein the first communicationchannel is a unidirectional communication channel characterized by theelectronic locking device being configured to receive data transmittedby the smart device and further characterized by the electronic lockingdevice being configured to forego attempts to transmit data via thefirst communication channel.
 12. The electronic locking device of claim11, wherein the second communication channel is a bidirectionalcommunication channel.